.TH mongod 1
.SH MONGOD
.SH SYNOPSIS
\fBmongod\f1 is the primary daemon process for the MongoDB
system. It handles data requests, manages data access, and performs
background management operations.
.PP
This document provides a complete overview of all command line options
for \fBmongod\f1\&. These command line options are primarily useful
for testing: In common operation, use the \fBconfiguration file
options\f1 to control the behavior of
your database.
.PP
\fBConfiguration File Settings and Command\-Line Options Mapping\f1
.PP
MongoDB disables support for TLS 1.0
encryption on systems where TLS 1.1+ is available.
.SH COMPATIBILITY
.PP
Deployments hosted in the following environments use \fBmongod\f1:
.RS
.IP \(bu 2
MongoDB Atlas (https://www.mongodb.com/docs/atlas?tck=docs_server): The fully
managed service for MongoDB deployments in the cloud
.RE
.PP
MongoDB Atlas manages the \fBmongod\f1 for all MongoDB Atlas deployments.
.RS
.IP \(bu 2
\fBMongoDB Enterprise\f1: The
subscription\-based, self\-managed version of MongoDB
.IP \(bu 2
\fBMongoDB Community\f1: The
source\-available, free\-to\-use, and self\-managed version of MongoDB
.RE
.SH CONSIDERATIONS
.RS
.IP \(bu 2
\fBmongod\f1\f1 includes a \fBFull Time Diagnostic Data Capture\f1 mechanism to assist MongoDB engineers with troubleshooting
deployments. If this thread fails, it terminates the originating process.
To avoid the most common failures, confirm that the user running the
process has permissions to create the FTDC \fBdiagnostic.data\f1
directory. For \fBmongod\f1 the directory is within
\fBstorage.dbPath\f1\f1\&. For \fBmongos\f1 it is parallel to \fBsystemLog.path\f1\f1\&.
.RE
.SH OPTIONS
.RS
.IP \(bu 2
MongoDB always enables journaling. As a result, MongoDB removes the
\fBstorage.journal.enabled\f1 option and the corresponding \fB\-\-journal\f1 and
\fB\-\-nojournal\f1 command\-line options.
.RE
.RS
.IP \(bu 2
MongoDB removes the \fB\-\-cpu\f1 command\-line option.
.RE
.RS
.IP \(bu 2
MongoDB removes the \fB\-\-serviceExecutor\f1 command\-line option and the
corresponding \fBnet.serviceExecutor\f1 configuration option.
.RE
.SS CORE OPTIONS
.PP
\fBmongod \-\-help\f1, \fBmongod \-h\f1
.RS
.PP
Returns information on the options and use of \fBmongod\f1\&.
.RE
.PP
\fBmongod \-\-version\f1
.RS
.PP
Returns the \fBmongod\f1 release number.
.RE
.PP
\fBmongod \-\-config\f1, \fBmongod \-f\f1
.RS
.PP
Specifies a configuration file for runtime configuration options. The
configuration file is the preferred method for runtime configuration of
\fBmongod\f1\&. The options are equivalent to the command\-line
configuration options. See \fBConfiguration File Options\f1 for
more information.
.PP
Ensure the configuration file uses ASCII encoding. The \fBmongod\f1
instance does not support configuration files with non\-ASCII encoding,
including UTF\-8.
.RE
.PP
\fBmongod \-\-configExpand\f1
.RS
.PP
\fIDefault\f1: none
.PP
Enables using \fBExpansion Directives\f1
in configuration files. Expansion directives allow you to set
externally sourced values for configuration file options.
.PP
\fB\-\-configExpand\f1\f1 supports the following expansion directives:
.RS
.IP \(bu 2
.RS
.IP \(bu 4
Value
.IP \(bu 4
Description
.RE
.IP \(bu 2
.RS
.IP \(bu 4
\fBnone\f1
.IP \(bu 4
Default. \fBmongod\f1 does not expand expansion directives.
\fBmongod\f1 fails to start if any configuration file settings
use expansion directives.
.RE
.IP \(bu 2
.RS
.IP \(bu 4
\fBrest\f1
.IP \(bu 4
\fBmongod\f1 expands \fB__rest\f1 expansion directives when
parsing the configuration file.
.RE
.IP \(bu 2
.RS
.IP \(bu 4
\fBexec\f1
.IP \(bu 4
\fBmongod\f1 expands \fB__exec\f1 expansion directives when
parsing the configuration file.
.RE
.RE
.PP
You can specify multiple expansion directives as a comma\-separated
list, for example: \fBrest, exec\f1\&. If the configuration file contains
expansion directives not specified to \fB\-\-configExpand\f1\f1, the \fBmongod\f1
returns an error and terminates.
.PP
See \fBExternally Sourced Configuration File Values\f1 for configuration files
for more information on expansion directives.
.RE
.PP
\fBmongod \-\-verbose\f1, \fBmongod \-v\f1
.RS
.PP
Increases the amount of internal reporting returned on standard output
or in log files. Increase the verbosity with the \fB\-v\f1 form by
including the option multiple times, for example: \fB\-vvvvv\f1\&.
.PP
Starting in version 4.2, MongoDB includes the Debug verbosity level
(1\-5) in the \fBlog messages\f1\&. For example,
if the verbosity level is 2, MongoDB logs \fBD2\f1\&. In previous
versions, MongoDB log messages only specified \fBD\f1 for Debug level.
.RE
.PP
\fBmongod \-\-quiet\f1
.RS
.PP
Runs \fBmongod\f1 in a quiet mode that attempts to limit the amount
of output.
.PP
This option suppresses:
.RS
.IP \(bu 2
output from \fBdatabase commands\f1
.IP \(bu 2
replication activity
.IP \(bu 2
connection accepted events
.IP \(bu 2
connection closed events
.RE
.RE
.PP
\fBmongod \-\-port\f1
.RS
.PP
\fIDefault\f1:
.RS
.IP \(bu 2
27017 if \fBmongod\f1 is not a shard member or a config server member
.IP \(bu 2
27018 if \fBmongod\f1 is a \fBshard member\f1\f1
.IP \(bu 2
27019 if \fBmongod\f1 is a \fBconfig server member\f1\f1
.RE
.PP
The TCP port on which the MongoDB instance listens for
client connections.
.PP
The \fB\-\-port\f1 option accepts a range of values between \fB0\f1 and \fB65535\f1\&.
Setting the port to \fB0\f1 configures \fBmongod\f1 to use an arbitrary port
assigned by the operating system.
.RE
.PP
\fBmongod \-\-bind_ip\f1
.RS
.PP
\fIDefault\f1: localhost
.PP
The hostnames and/or IP addresses and/or full Unix domain socket
paths on which \fBmongod\f1 should listen for client connections. You
may attach \fBmongod\f1 to any interface. To bind to multiple
addresses, enter a list of comma\-separated values.
.PP
You can specify both IPv4 and IPv6 addresses, or hostnames that
resolve to an IPv4 or IPv6 address.
.PP
If specifying an IPv6 address \fIor\f1 a hostname that resolves to an
IPv6 address to \fB\-\-bind_ip\f1\f1, you must start \fBmongod\f1 with
\fB\-\-ipv6\f1\f1 to enable IPv6 support. Specifying an IPv6 address
to \fB\-\-bind_ip\f1\f1 does not enable IPv6 support.
.PP
If specifying a
link\-local IPv6 address (https://en.wikipedia.org/wiki/Link\-local_address#IPv6)
(\fBfe80::/10\f1), you must append the
zone index (https://en.wikipedia.org/wiki/IPv6_address#Scoped_literal_IPv6_addresses_(with_zone_index))
to that address (i.e. \fBfe80::<address>%<adapter\-name>\f1).
.PP
To avoid configuration updates due to IP address changes, use DNS
hostnames instead of IP addresses. It is particularly important to
use a DNS hostname instead of an IP address when configuring replica
set members or sharded cluster members.
.PP
Use hostnames instead of IP addresses to configure clusters across a
split network horizon. Starting in MongoDB 5.0, nodes that are only
configured with an IP address fail startup validation and do not start.
.PP
Before you bind your instance to a publicly\-accessible IP address,
you must secure your cluster from unauthorized access. For a complete
list of security recommendations, see
\fBSecurity Checklist\f1\&. At minimum, consider
\fBenabling authentication\f1 and \fBhardening
network infrastructure\f1\&.
.PP
For more information about IP Binding, refer to the
\fBIP Binding\f1 documentation.
.PP
To bind to all IPv4 addresses, enter \fB0.0.0.0\f1\&.
.PP
To bind to all IPv4 and IPv6 addresses, enter \fB::,0.0.0.0\f1 or
an asterisk \fB"*"\f1 (enclose the asterisk in quotes to avoid filename
pattern expansion). Alternatively, use the \fBnet.bindIpAll\f1\f1 setting.
.RS
.IP \(bu 2
\fB\-\-bind_ip\f1 and \fB\-\-bind_ip_all\f1 are mutually exclusive.
Specifying both options causes \fBmongod\f1 to throw an error and
terminate.
.IP \(bu 2
The command\-line option \fB\-\-bind\f1 overrides the configuration
file setting \fBnet.bindIp\f1\f1\&.
.RE
.RE
.PP
\fBmongod \-\-bind_ip_all\f1
.RS
.PP
If specified, the \fBmongod\f1 instance binds to all IPv4
addresses (i.e. \fB0.0.0.0\f1). If \fBmongod\f1 starts with
\fB\-\-ipv6\f1\f1, \fB\-\-bind_ip_all\f1\f1 also binds to all IPv6 addresses
(i.e. \fB::\f1).
.PP
\fBmongod\f1 only supports IPv6 if started with \fB\-\-ipv6\f1\f1\&. Specifying
\fB\-\-bind_ip_all\f1\f1 alone does not enable IPv6 support.
.PP
Before you bind your instance to a publicly\-accessible IP address,
you must secure your cluster from unauthorized access. For a complete
list of security recommendations, see
\fBSecurity Checklist\f1\&. At minimum, consider
\fBenabling authentication\f1 and \fBhardening
network infrastructure\f1\&.
.PP
For more information about IP Binding, refer to the
\fBIP Binding\f1 documentation.
.PP
Alternatively, you can set the \fB\-\-bind_ip\f1 option to \fB::,0.0.0.0\f1
or to an asterisk \fB"*"\f1 (enclose the asterisk in quotes to avoid filename
pattern expansion).
.PP
\fB\-\-bind_ip\f1 and \fB\-\-bind_ip_all\f1 are mutually exclusive. That
is, you can specify one or the other, but not both.
.RE
.PP
\fBmongod \-\-clusterIpSourceAllowlist\f1
.RS
.PP
A list of IP addresses/CIDR (Classless Inter\-Domain Routing (https://tools.ietf.org/html/rfc4632)) ranges against which the
\fBmongod\f1 validates authentication requests from other members of
the replica set and, if part of a sharded cluster, the \fBmongos\f1\f1
instances. The \fBmongod\f1 verifies that the originating IP is
either explicitly in the list or belongs to a CIDR range in the list. If the
IP address is not present, the server does not authenticate the
\fBmongod\f1 or \fBmongos\f1\f1\&.
.PP
\fB\-\-clusterIpSourceAllowlist\f1\f1 has no effect on a \fBmongod\f1 started without
\fBauthentication\f1\&.
.PP
\fB\-\-clusterIpSourceAllowlist\f1\f1 accepts multiple comma\-separated IPv4/6 addresses or Classless
Inter\-Domain Routing (CIDR (https://tools.ietf.org/html/rfc4632)) ranges:
.PP
.EX
  mongod \-\-clusterIpSourceAllowlist 192.0.2.0/24,127.0.0.1,::1
.EE
.PP
Ensure \fB\-\-clusterIpSourceAllowlist\f1\f1 includes the IP address \fIor\f1 CIDR ranges that include the
IP address of each replica set member or \fBmongos\f1\f1 in the
deployment to ensure healthy communication between cluster components.
.RE
.PP
\fBmongod \-\-clusterIpSourceWhitelist\f1
.RS
.PP
\fIDeprecated in version 5.0:\f1
Use \fB\-\-clusterIpSourceAllowlist\f1\f1 instead.
.PP
A list of IP addresses/CIDR (Classless Inter\-Domain Routing (https://tools.ietf.org/html/rfc4632)) ranges against which the
\fBmongod\f1 validates authentication requests from other members of
the replica set and, if part of a sharded cluster, the \fBmongos\f1\f1
instances. The \fBmongod\f1 verifies that the originating IP is
either explicitly in the list or belongs to a CIDR range in the list. If the
IP address is not present, the server does not authenticate the
\fBmongod\f1 or \fBmongos\f1\f1\&.
.PP
\fB\-\-clusterIpSourceWhitelist\f1\f1 has no effect on a \fBmongod\f1 started without
\fBauthentication\f1\&.
.PP
\fB\-\-clusterIpSourceWhitelist\f1\f1 accepts multiple comma\-separated IPv4/6 addresses or Classless
Inter\-Domain Routing (CIDR (https://tools.ietf.org/html/rfc4632)) ranges:
.PP
.EX
  mongod \-\-clusterIpSourceWhitelist 192.0.2.0/24,127.0.0.1,::1
.EE
.PP
Ensure \fB\-\-clusterIpSourceWhitelist\f1\f1 includes the IP address \fIor\f1 CIDR ranges that include the
IP address of each replica set member or \fBmongos\f1\f1 in the
deployment to ensure healthy communication between cluster components.
.RE
.PP
\fBmongod \-\-ipv6\f1
.RS
.PP
Enables IPv6 support. \fBmongod\f1 disables IPv6 support by default.
.PP
Setting \fB\-\-ipv6\f1\f1 does \fInot\f1 direct the \fBmongod\f1 to listen on any
local IPv6 addresses or interfaces. To configure the \fBmongod\f1 to
listen on an IPv6 interface, you must either:
.RS
.IP \(bu 2
Configure \fB\-\-bind_ip\f1\f1 with one or more IPv6 addresses or
hostnames that resolve to IPv6 addresses, \fBor\f1
.IP \(bu 2
Set \fB\-\-bind_ip_all\f1\f1 to \fBtrue\f1\&.
.RE
.RE
.PP
\fBmongod \-\-listenBacklog\f1
.RS
.PP
\fIDefault\f1: Target system \fBSOMAXCONN\f1 constant
.PP
The maximum number of connections that can exist in the listen
queue.
.PP
Consult your local system\(aqs documentation to understand the
limitations and configuration requirements before using this
parameter.
.PP
To prevent undefined behavior, specify a value for this
parameter between \fB1\f1 and the local system \fBSOMAXCONN\f1
constant.
.PP
The default value for the \fBlistenBacklog\f1 parameter is set at
compile time to the target system \fBSOMAXCONN\f1 constant.
\fBSOMAXCONN\f1 is the maximum valid value that is documented for
the \fIbacklog\f1 parameter to the \fIlisten\f1 system call.
.PP
Some systems may interpret \fBSOMAXCONN\f1 symbolically, and others
numerically. The actual \fIlisten backlog\f1 applied in practice may
differ from any numeric interpretation of the \fBSOMAXCONN\f1 constant
or argument to \fB\-\-listenBacklog\f1, and may also be constrained by
system settings like \fBnet.core.somaxconn\f1 on Linux.
.PP
Passing a value for the \fBlistenBacklog\f1 parameter that exceeds the
\fBSOMAXCONN\f1 constant for the local system is, by the letter of the
standards, undefined behavior. Higher values may be silently integer
truncated, may be ignored, may cause unexpected resource
consumption, or have other adverse consequences.
.PP
On systems with workloads that exhibit connection spikes, for which
it is empirically known that the local system can honor higher
values for the \fIbacklog\f1 parameter than the \fBSOMAXCONN\f1 constant,
setting the \fBlistenBacklog\f1 parameter to a higher value may reduce
operation latency as observed by the client by reducing the number
of connections which are forced into a backoff state.
.RE
.PP
\fBmongod \-\-maxConns\f1
.RS
.PP
The maximum number of simultaneous connections that \fBmongod\f1
accepts. This setting has no effect if it is higher than your operating
system\(aqs configured maximum connection tracking threshold.
.PP
Do not assign too low of a value to this option, or you will
encounter errors during normal application operation.
.RE
.PP
\fBmongod \-\-logpath\f1
.RS
.PP
Sends all diagnostic logging information to a log file instead of to
standard output or to the host\(aqs \fBsyslog\f1 system. MongoDB creates
the log file at the path you specify.
.PP
By default, MongoDB moves any existing log file rather than overwriting
it. To instead append to the log file, set the \fB\-\-logappend\f1\f1 option.
.RE
.PP
\fBmongod \-\-syslog\f1
.RS
.PP
Sends all logging output to the host\(aqs \fBsyslog\f1 system rather
than to standard output or to a log file (\fB\-\-logpath\f1\f1).
.PP
The \fB\-\-syslog\f1\f1 option is not supported on Windows.
.PP
The \fBsyslog\f1 daemon generates timestamps when it logs a message, not
when MongoDB issues the message. This can lead to misleading timestamps
for log entries, especially when the system is under heavy load. We
recommend using the \fB\-\-logpath\f1\f1 option for production systems to
ensure accurate timestamps.
.PP
MongoDB includes the \fBcomponent\f1 in its log
messages to \fBsyslog\f1\&.
.PP
.EX
  ...  ACCESS   [repl writer worker 5] Unsupported modification to roles collection ...
.EE
.RE
.PP
\fBmongod \-\-syslogFacility\f1
.RS
.PP
\fIDefault\f1: user
.PP
Specifies the facility level used when logging messages to syslog.
The value you specify must be supported by your
operating system\(aqs implementation of syslog. To use this option, you
must  enable the \fB\-\-syslog\f1\f1 option.
.RE
.PP
\fBmongod \-\-logappend\f1
.RS
.PP
Appends new entries to the end of the existing log file when the \fBmongod\f1
instance restarts. Without this option, \fBmongod\f1 backs up the
existing log and create a new file.
.RE
.PP
\fBmongod \-\-logRotate\f1
.RS
.PP
\fIDefault\f1: rename
.PP
Determines the behavior for the \fBlogRotate\f1\f1 command when
rotating the server log and/or the audit log. Specify either
\fBrename\f1 or \fBreopen\f1:
.RS
.IP \(bu 2
\fBrename\f1 renames the log file.
.IP \(bu 2
\fBreopen\f1 closes and reopens the log file following the typical
Linux/Unix log rotate behavior. Use \fBreopen\f1 when using the
Linux/Unix logrotate utility to avoid log loss.
.IP
If you specify \fBreopen\f1, you must also use \fB\-\-logappend\f1\f1\&.
.RE
.RE
.PP
\fBmongod \-\-timeStampFormat\f1
.RS
.PP
\fIDefault\f1: iso8601\-local
.PP
The time format for timestamps in log messages. Specify one of the
following values:
.RS
.IP \(bu 2
.RS
.IP \(bu 4
Value
.IP \(bu 4
Description
.RE
.IP \(bu 2
.RS
.IP \(bu 4
\fBiso8601\-utc\f1
.IP \(bu 4
Displays timestamps in Coordinated Universal Time (UTC) in the
ISO\-8601 format. For example, for New York at the start of the
Epoch: \fB1970\-01\-01T00:00:00.000Z\f1
.RE
.IP \(bu 2
.RS
.IP \(bu 4
\fBiso8601\-local\f1
.IP \(bu 4
Displays timestamps in local time in the ISO\-8601
format. For example, for New York at the start of the Epoch:
\fB1969\-12\-31T19:00:00.000\-05:00\f1
.RE
.RE
.PP
\fB\-\-timeStampFormat\f1\f1 no longer supports \fBctime\f1\&. An example of \fBctime\f1
formatted date is: \fBWed Dec 31 18:17:54.811\f1\&.
.RE
.PP
\fBmongod \-\-traceExceptions\f1
.RS
.PP
For internal diagnostic use only.
.RE
.PP
\fBmongod \-\-pidfilepath\f1
.RS
.PP
Specifies a file location to store the process ID (PID) of the \fBmongod\f1
process. The user running the \fBmongod\f1 or \fBmongos\f1
process must be able to write to this path. If the \fB\-\-pidfilepath\f1\f1 option is not
specified, the process does not create a PID file. This option is generally
only useful in combination with the \fB\-\-fork\f1\f1 option.
.PP
On Linux, PID file management is generally the responsibility of
your distro\(aqs init system: usually a service file in the \fB/etc/init.d\f1
directory, or a systemd unit file registered with \fBsystemctl\f1\&. Only
use the \fB\-\-pidfilepath\f1\f1 option if you are not using one of these init
systems. For more information, please see the respective
\fBInstallation Guide\f1 for your operating system.
.PP
On macOS, PID file management is generally handled by \fBbrew\f1\&. Only use
the \fB\-\-pidfilepath\f1\f1 option if you are not using \fBbrew\f1 on your macOS system.
For more information, please see the respective Installation
Guide for your operating system.
.RE
.PP
\fBmongod \-\-keyFile\f1
.RS
.PP
Specifies the path to a key file that stores the shared secret
that MongoDB instances use to authenticate to each other in a
\fBsharded cluster\f1 or \fBreplica set\f1\&. \fB\-\-keyFile\f1\f1 implies
\fB\-\-auth\f1\f1\&. See \fBInternal/Membership Authentication\f1 for more
information.
.PP
\fBKeyfiles for internal membership authentication\f1 use YAML format to allow for multiple keys in a
keyfile. The YAML format accepts either:
.RS
.IP \(bu 2
A single key string (same as in earlier versions)
.IP \(bu 2
A sequence of key strings
.RE
.PP
The YAML format is compatible with the existing single\-key
keyfiles that use the text file format.
.RE
.PP
\fBmongod \-\-setParameter\f1
.RS
.PP
Specifies one of the MongoDB parameters described in
\fBMongoDB Server Parameters\f1\&. You can specify multiple \fBsetParameter\f1
fields.
.RE
.PP
\fBmongod \-\-nounixsocket\f1
.RS
.PP
Disables listening on the UNIX domain socket. \fB\-\-nounixsocket\f1\f1 applies only
to Unix\-based systems.
.PP
The \fBmongod\f1 process
always listens on the UNIX socket unless one of the following is true:
.RS
.IP \(bu 2
\fB\-\-nounixsocket\f1\f1 is set
.IP \(bu 2
\fBnet.bindIp\f1\f1 is not set
.IP \(bu 2
\fBnet.bindIp\f1\f1 does not specify \fBlocalhost\f1 or its associated IP address
.RE
.PP
\fBmongod\f1 installed from official \fB\&.deb\f1 and \fB\&.rpm\f1 packages
have the \fBbind_ip\f1 configuration set to \fB127.0.0.1\f1 by
default.
.RE
.PP
\fBmongod \-\-unixSocketPrefix\f1
.RS
.PP
\fIDefault\f1: /tmp
.PP
The path for the UNIX socket. \fB\-\-unixSocketPrefix\f1\f1 applies only
to Unix\-based systems.
.PP
If this option has no value, the
\fBmongod\f1 process creates a socket with \fB/tmp\f1 as a prefix. MongoDB
creates and listens on a UNIX socket unless one of the following is true:
.RS
.IP \(bu 2
\fBnet.unixDomainSocket.enabled\f1\f1 is \fBfalse\f1
.IP \(bu 2
\fB\-\-nounixsocket\f1\f1 is set
.IP \(bu 2
\fBnet.bindIp\f1\f1 is not set
.IP \(bu 2
\fBnet.bindIp\f1\f1 does not specify \fBlocalhost\f1 or its associated IP address
.RE
.RE
.PP
\fBmongod \-\-filePermissions\f1
.RS
.PP
\fIDefault\f1: \fB0700\f1
.PP
Sets the permission for the UNIX domain socket file.
.PP
\fB\-\-filePermissions\f1\f1 applies only to Unix\-based systems.
.RE
.PP
\fBmongod \-\-fork\f1
.RS
.PP
Enables a \fBdaemon\f1 mode that runs the \fBmongod\f1 process in the
background. The \fB\-\-fork\f1\f1 option is not supported on Windows.
.PP
By default \fBmongod\f1 does not run as a daemon. You run \fBmongod\f1 as
a daemon by using either \fB\-\-fork\f1\f1 or a controlling process
that handles daemonization, such as \fBupstart\f1 or \fBsystemd\f1\&.
.PP
To use \fB\-\-fork\f1\f1, configure log output for the \fBmongod\f1 with one of the following:
.RS
.IP \(bu 2
\fB\-\-logpath\f1\f1
.IP \(bu 2
\fB\-\-syslog\f1\f1
.RE
.RE
.PP
\fBmongod \-\-auth\f1
.RS
.PP
Enables authorization to control user\(aqs access to database resources
and operations. When authorization is enabled, MongoDB requires all
clients to authenticate themselves first in order to determine the
access for the client.
.PP
To configure users, use the \fBmongosh\f1\f1 client. If no users
exist, the localhost interface has access to the
database until you create the first user.
.PP
See \fBSecurity\f1 for more information.
.RE
.PP
\fBmongod \-\-noauth\f1
.RS
.PP
Disables authentication. Currently the default. Exists for future
compatibility and clarity.
.RE
.PP
\fBmongod \-\-transitionToAuth\f1
.RS
.PP
Allows the \fBmongod\f1 to accept and create authenticated and
non\-authenticated connections to and from other \fBmongod\f1
and \fBmongos\f1\f1 instances in the deployment. Used for
performing rolling transition of replica sets or sharded clusters
from a no\-auth configuration to \fBinternal authentication\f1\&. Requires specifying a \fBinternal
authentication\f1 mechanism such as
\fB\-\-keyFile\f1\f1\&.
.PP
For example, if using \fBkeyfiles\f1 for
\fBinternal authentication\f1, the \fBmongod\f1 creates
an authenticated connection with any \fBmongod\f1 or \fBmongos\f1\f1
in the deployment using a matching keyfile. If the security mechanisms do
not match, the \fBmongod\f1 utilizes a non\-authenticated connection instead.
.PP
A \fBmongod\f1 running with \fB\-\-transitionToAuth\f1\f1 does not enforce \fBuser access
controls\f1\&. Users may connect to your deployment without any
access control checks and perform read, write, and administrative operations.
.PP
A \fBmongod\f1 running with \fBinternal authentication\f1 and \fIwithout\f1 \fB\-\-transitionToAuth\f1\f1 requires clients to connect
using \fBuser access controls\f1\&. Update clients to
connect to the \fBmongod\f1 using the appropriate \fBuser\f1
prior to restarting \fBmongod\f1 without \fB\-\-transitionToAuth\f1\f1\&.
.RE
.PP
\fBmongod \-\-sysinfo\f1
.RS
.PP
Returns diagnostic system information and then exits. The
information provides the page size, the number of physical pages,
and the number of available physical pages.
.RE
.PP
\fBmongod \-\-noscripting\f1
.RS
.PP
Disables the scripting engine.
.RE
.PP
\fBmongod \-\-notablescan\f1
.RS
.PP
Forbids operations that require a collection scan. See \fBnotablescan\f1\f1 for additional information.
.RE
.PP
\fBmongod \-\-shutdown\f1
.RS
.PP
The \fB\-\-shutdown\f1\f1 option cleanly and safely terminates the \fBmongod\f1
process. When invoking \fBmongod\f1 with this option you must set the
\fB\-\-dbpath\f1\f1 option either directly or by way of the
\fBconfiguration file\f1 and the
\fB\-\-config\f1\f1 option.
.PP
The \fB\-\-shutdown\f1\f1 option is available only on Linux systems.
.PP
For additional ways to shut down, see also \fBStop mongod\f1 Processes\f1\&.
.RE
.PP
\fBmongod \-\-redactClientLogData\f1
.RS
.PP
\fIAvailable in MongoDB Enterprise only.\f1
.PP
A \fBmongod\f1 running with \fB\-\-redactClientLogData\f1\f1 redacts any message accompanying a given
log event before logging. This prevents the \fBmongod\f1 from writing
potentially sensitive data stored on the database to the diagnostic log.
Metadata such as error or operation codes, line numbers, and source file
names are still visible in the logs.
.PP
Use \fB\-\-redactClientLogData\f1\f1 in conjunction with
\fBEncryption at Rest\f1 and
\fBTLS/SSL (Transport Encryption)\f1 to assist compliance with
regulatory requirements.
.PP
For example, a MongoDB deployment might store Personally Identifiable
Information (PII) in one or more collections. The \fBmongod\f1 logs events
such as those related to CRUD operations, sharding metadata, etc. It is
possible that the \fBmongod\f1 may expose PII as a part of these logging
operations. A \fBmongod\f1 running with \fB\-\-redactClientLogData\f1\f1 removes any message
accompanying these events before being output to the log, effectively
removing the PII.
.PP
Diagnostics on a \fBmongod\f1 running with \fB\-\-redactClientLogData\f1\f1 may be more difficult
due to the lack of data related to a log event. See the
\fBprocess logging\f1 manual page for an
example of the effect of \fB\-\-redactClientLogData\f1\f1 on log output.
.PP
On a running \fBmongod\f1, use \fBsetParameter\f1\f1 with the
\fBredactClientLogData\f1\f1 parameter to configure this setting.
.RE
.PP
\fBmongod \-\-networkMessageCompressors\f1
.RS
.PP
\fIDefault\f1: snappy,zstd,zlib
.PP
Specifies the default compressor(s) to use for
communication between this \fBmongod\f1 instance and:
.RS
.IP \(bu 2
other members of the deployment if the instance is part of a replica set or a sharded cluster
.IP \(bu 2
\fBmongosh\f1\f1
.IP \(bu 2
drivers that support the \fBOP_COMPRESSED\f1 message format.
.RE
.PP
MongoDB supports the following compressors:
.RS
.IP \(bu 2
\fBsnappy\f1
.IP \(bu 2
\fBzlib\f1
.IP \(bu 2
\fBzstd\f1
.RE
.PP
Both \fBmongod\f1 and \fBmongos\f1\f1 instances default to
\fBsnappy,zstd,zlib\f1 compressors, in that order.
.PP
To disable network compression, set the value to \fBdisabled\f1\&.
.PP
Messages are compressed when both parties enable network
compression. Otherwise, messages between the parties are
uncompressed.
.PP
If you specify multiple compressors, then the order in which you list
the compressors matter as well as the communication initiator. For
example, if \fBmongosh\f1\f1 specifies the following network
compressors \fBzlib,snappy\f1 and the \fBmongod\f1\f1 specifies
\fBsnappy,zlib\f1, messages between \fBmongosh\f1\f1 and
\fBmongod\f1\f1 uses \fBzlib\f1\&.
.PP
If the parties do not share at least one common compressor, messages
between the parties are uncompressed. For example, if
\fBmongosh\f1\f1 specifies the network compressor
\fBzlib\f1 and \fBmongod\f1\f1 specifies \fBsnappy\f1, messages
between \fBmongosh\f1\f1 and \fBmongod\f1\f1 are not
compressed.
.RE
.PP
\fBmongod \-\-timeZoneInfo\f1
.RS
.PP
The full path from which to load the time zone database. If this option
is not provided, then MongoDB uses its built\-in time zone database.
.PP
The configuration file included with Linux and macOS packages sets the
time zone database path to \fB/usr/share/zoneinfo\f1 by default.
.PP
The built\-in time zone database is a copy of the Olson/IANA time zone
database (https://www.iana.org/time\-zones)\&. It is updated along with
MongoDB releases, but the time zone database release cycle
differs from the MongoDB release cycle. The most recent release of
the time zone database is available on our download site (https://downloads.mongodb.org/olson_tz_db/timezonedb\-latest.zip)\&.
.PP
.EX
  wget https://downloads.mongodb.org/olson_tz_db/timezonedb\-latest.zip
  unzip timezonedb\-latest.zip
  mongod \-\-timeZoneInfo timezonedb\-2017b/
.EE
.PP
MongoDB uses the third party timelib (https://github.com/derickr/timelib) library to provide accurate
conversions between timezones. Due to a recent update, \fBtimelib\f1
could create inaccurate time zone conversions in older versions of
MongoDB.
.PP
To explicitly link to the time zone database in versions of MongoDB
prior to 5.0, download the time zone database (https://downloads.mongodb.org/olson_tz_db/timezonedb\-latest.zip)\&.
and use the \fBtimeZoneInfo\f1\f1 parameter.
.PP
\fBprocessManagement.timeZoneInfo\f1\f1\&.
.RE
.PP
\fBmongod \-\-outputConfig\f1
.RS
.PP
Outputs the \fBmongod\f1 instance\(aqs configuration options, formatted
in YAML, to \fBstdout\f1 and exits the \fBmongod\f1 instance. For
configuration options that uses \fBExternally Sourced Configuration File Values\f1,
\fB\-\-outputConfig\f1\f1 returns the resolved value for those options.
.PP
This may include any configured passwords or secrets previously
obfuscated through the external source.
.PP
For usage examples, see:
.RS
.IP \(bu 2
\fBOutput the Configuration File with Resolved Expansion Directive Values\f1
.IP \(bu 2
\fBConvert Command\-Line Options to YAML\f1
.RE
.RE
.SS LDAP AUTHENTICATION OR AUTHORIZATION OPTIONS
.PP
\fBmongod \-\-ldapServers\f1
.RS
.PP
\fIAvailable in MongoDB Enterprise only.\f1
.PP
The LDAP server against which the \fBmongod\f1 authenticates users or
determines what actions a user is authorized to perform on a given
database. If the LDAP server specified has any replicated instances,
you may specify the host and port of each replicated server in a
comma\-delimited list.
.PP
If your LDAP infrastructure partitions the LDAP directory over multiple LDAP
servers, specify \fIone\f1 LDAP server or any of its replicated instances to
\fB\-\-ldapServers\f1\f1\&. MongoDB supports following LDAP referrals as defined in RFC 4511
4.1.10 (https://www.rfc\-editor.org/rfc/rfc4511.txt)\&. Do not use \fB\-\-ldapServers\f1\f1
for listing every LDAP server in your infrastructure.
.PP
This setting can be configured on a running \fBmongod\f1 using
\fBsetParameter\f1\f1\&.
.PP
If unset, \fBmongod\f1 cannot use \fBLDAP authentication or authorization\f1\&.
.RE
.PP
\fBmongod \-\-ldapValidateLDAPServerConfig\f1
.RS
.PP
\fIAvailable in MongoDB Enterprise\f1
.PP
A flag that determines if the \fBmongod\f1 instance checks
the availability of the \fBLDAP server(s)\f1\f1 as part of its startup:
.RS
.IP \(bu 2
If \fBtrue\f1, the \fBmongod\f1 instance performs the
availability check and only continues to start up if the LDAP
server is available.
.IP \(bu 2
If \fBfalse\f1, the \fBmongod\f1 instance skips the
availability check; i.e. the instance starts up even if the LDAP
server is unavailable.
.RE
.RE
.PP
\fBmongod \-\-ldapQueryUser\f1
.RS
.PP
\fIAvailable in MongoDB Enterprise only.\f1
.PP
The identity with which \fBmongod\f1 binds as, when connecting to or
performing queries on an LDAP server.
.PP
Only required if any of the following are true:
.RS
.IP \(bu 2
Using \fBLDAP authorization\f1\&.
.IP \(bu 2
Using an LDAP query for \fBusername transformation\f1\f1\&.
.IP \(bu 2
The LDAP server disallows anonymous binds
.RE
.PP
You must use \fB\-\-ldapQueryUser\f1\f1 with \fB\-\-ldapQueryPassword\f1\f1\&.
.PP
If unset, \fBmongod\f1 doesn\(aqt attempt to bind to the LDAP server.
.PP
This setting can be configured on a running \fBmongod\f1 using
\fBsetParameter\f1\f1\&.
.PP
Windows MongoDB deployments can use \fB\-\-ldapBindWithOSDefaults\f1\f1
instead of \fB\-\-ldapQueryUser\f1\f1 and \fB\-\-ldapQueryPassword\f1\f1\&. You cannot specify
both \fB\-\-ldapQueryUser\f1\f1 and \fB\-\-ldapBindWithOSDefaults\f1\f1 at the same time.
.RE
.PP
\fIAvailable in MongoDB Enterprise only.\f1
.PP
The password used to bind to an LDAP server when using
\fB\-\-ldapQueryUser\f1\f1\&. You must use \fB\-\-ldapQueryPassword\f1\f1 with
\fB\-\-ldapQueryUser\f1\f1\&.
.PP
If not set, \fBmongod\f1\f1 does not attempt to bind to the LDAP server.
.PP
You can configure this setting on a running \fBmongod\f1\f1 using
\fBsetParameter\f1\f1\&.
.PP
The \fBldapQueryPassword\f1 \fBsetParameter\f1\f1 command accepts either a
string or an array of strings. If \fBldapQueryPassword\f1 is set to an array,
MongoDB tries each password in order until one succeeds. Use a password array
to roll over the LDAP account password without downtime.
.PP
Windows MongoDB deployments can use \fB\-\-ldapBindWithOSDefaults\f1\f1
instead of \fB\-\-ldapQueryUser\f1\f1 and \fB\-\-ldapQueryPassword\f1\f1\&.
You cannot specify both \fB\-\-ldapQueryPassword\f1\f1 and
\fB\-\-ldapBindWithOSDefaults\f1\f1 at the same time.
.PP
\fBmongod \-\-ldapBindWithOSDefaults\f1
.RS
.PP
\fIDefault\f1: false
.PP
Available in MongoDB Enterprise for the Windows platform only.
.PP
Allows \fBmongod\f1 to authenticate, or bind, using your Windows login
credentials when connecting to the LDAP server.
.PP
Only required if:
.RS
.IP \(bu 2
Using \fBLDAP authorization\f1\&.
.IP \(bu 2
Using an LDAP query for \fBusername transformation\f1\f1\&.
.IP \(bu 2
The LDAP server disallows anonymous binds
.RE
.PP
Use \fB\-\-ldapBindWithOSDefaults\f1\f1 to replace \fB\-\-ldapQueryUser\f1\f1 and
\fB\-\-ldapQueryPassword\f1\f1\&.
.RE
.PP
\fBmongod \-\-ldapBindMethod\f1
.RS
.PP
\fIDefault\f1: simple
.PP
\fIAvailable in MongoDB Enterprise only.\f1
.PP
The method \fBmongod\f1 uses to authenticate to an LDAP server.
Use with \fB\-\-ldapQueryUser\f1\f1 and \fB\-\-ldapQueryPassword\f1\f1 to
connect to the LDAP server.
.PP
\fB\-\-ldapBindMethod\f1\f1 supports the following values:
.RS
.IP \(bu 2
\fBsimple\f1 \- \fBmongod\f1 uses simple authentication.
.IP \(bu 2
\fBsasl\f1 \- \fBmongod\f1 uses SASL protocol for authentication
.RE
.PP
If you specify \fBsasl\f1, you can configure the available SASL mechanisms
using \fB\-\-ldapBindSaslMechanisms\f1\f1\&. \fBmongod\f1 defaults to
using \fBDIGEST\-MD5\f1 mechanism.
.RE
.PP
\fBmongod \-\-ldapBindSaslMechanisms\f1
.RS
.PP
\fIDefault\f1: DIGEST\-MD5
.PP
\fIAvailable in MongoDB Enterprise only.\f1
.PP
A comma\-separated list of SASL mechanisms \fBmongod\f1 can
use when authenticating to the LDAP server. The \fBmongod\f1 and the
LDAP server must agree on at least one mechanism. The \fBmongod\f1
dynamically loads any SASL mechanism libraries installed on the host
machine at runtime.
.PP
Install and configure the appropriate libraries for the selected
SASL mechanism(s) on both the \fBmongod\f1 host and the remote
LDAP server host. Your operating system may include certain SASL
libraries by default. Defer to the documentation associated with each
SASL mechanism for guidance on installation and configuration.
.PP
If using the \fBGSSAPI\f1 SASL mechanism for use with
\fBKerberos Authentication\f1, verify the following for the
\fBmongod\f1 host machine:
.PP
\fBLinux\f1\f1
.RS
.RS
.IP \(bu 2
The \fBKRB5_CLIENT_KTNAME\f1 environment
variable resolves to the name of the client \fBLinux Keytab Files\f1
for the host machine. For more on Kerberos environment
variables, please defer to the
Kerberos documentation (https://web.mit.edu/kerberos/krb5\-1.13/doc/admin/env_variables.html)\&.
.IP \(bu 2
The client keytab includes a
\fBUser Principal\f1 for the \fBmongod\f1 to use when
connecting to the LDAP server and execute LDAP queries.
.RE
.RE
.PP
\fBWindows\f1\f1
.RS
.PP
If connecting to an Active Directory server, the Windows
Kerberos configuration automatically generates a
Ticket\-Granting\-Ticket (https://msdn.microsoft.com/en\-us/library/windows/desktop/aa380510(v=vs.85).aspx)
when the user logs onto the system. Set \fB\-\-ldapBindWithOSDefaults\f1\f1 to
\fBtrue\f1 to allow \fBmongod\f1 to use the generated credentials when
connecting to the Active Directory server and execute queries.
.RE
.PP
Set \fB\-\-ldapBindMethod\f1\f1 to \fBsasl\f1 to use this option.
.PP
For a complete list of SASL mechanisms see the
IANA listing (http://www.iana.org/assignments/sasl\-mechanisms/sasl\-mechanisms.xhtml)\&.
Defer to the documentation for your LDAP or Active Directory
service for identifying the SASL mechanisms compatible with the
service.
.PP
MongoDB is not a source of SASL mechanism libraries, nor
is the MongoDB documentation a definitive source for
installing or configuring any given SASL mechanism. For
documentation and support, defer to the SASL mechanism
library vendor or owner.
.PP
For more information on SASL, defer to the following resources:
.RS
.IP \(bu 2
For Linux, please see the Cyrus SASL documentation (https://www.cyrusimap.org/sasl/)\&.
.IP \(bu 2
For Windows, please see the Windows SASL documentation (https://msdn.microsoft.com/en\-us/library/cc223500.aspx)\&.
.RE
.RE
.PP
\fBmongod \-\-ldapTransportSecurity\f1
.RS
.PP
\fIDefault\f1: tls
.PP
\fIAvailable in MongoDB Enterprise only.\f1
.PP
By default, \fBmongod\f1 creates a TLS/SSL secured connection to the LDAP
server.
.PP
For Linux deployments, you must configure the appropriate TLS Options in
\fB/etc/openldap/ldap.conf\f1 file. Your operating system\(aqs package manager
creates this file as part of the MongoDB Enterprise installation, via the
\fBlibldap\f1 dependency. See the documentation for \fBTLS Options\f1 in the
ldap.conf OpenLDAP documentation (http://www.openldap.org/software/man.cgi?query=ldap.conf&manpath=OpenLDAP+2.4\-Release)
for more complete instructions.
.PP
For Windows deployment, you must add the LDAP server CA certificates to the
Windows certificate management tool. The exact name and functionality of the
tool may vary depending on operating system version. Please see the
documentation for your version of Windows for more information on
certificate management.
.PP
Set \fB\-\-ldapTransportSecurity\f1\f1 to \fBnone\f1 to disable TLS/SSL between \fBmongod\f1 and the LDAP
server.
.PP
Setting \fB\-\-ldapTransportSecurity\f1\f1 to \fBnone\f1 transmits plaintext information and possibly
credentials between \fBmongod\f1 and the LDAP server.
.RE
.PP
\fBmongod \-\-ldapTimeoutMS\f1
.RS
.PP
\fIDefault\f1: 10000
.PP
\fIAvailable in MongoDB Enterprise only.\f1
.PP
The amount of time in milliseconds \fBmongod\f1 should wait for an LDAP server
to respond to a request.
.PP
Increasing the value of \fB\-\-ldapTimeoutMS\f1\f1 may prevent connection failure between the
MongoDB server and the LDAP server, if the source of the failure is a
connection timeout. Decreasing the value of \fB\-\-ldapTimeoutMS\f1\f1 reduces the time
MongoDB waits for a response from the LDAP server.
.PP
This setting can be configured on a running \fBmongod\f1 using
\fBsetParameter\f1\f1\&.
.RE
.PP
\fBmongod \-\-ldapRetryCount\f1
.RS
.PP
\fIDefault\f1: 0
.PP
\fIAvailable in MongoDB Enterprise only.\f1
.PP
Number of operation retries by the server LDAP manager after a
network error.
.RE
.PP
\fBmongod \-\-ldapUserToDNMapping\f1
.RS
.PP
\fIAvailable in MongoDB Enterprise only.\f1
.PP
Maps the username provided to \fBmongod\f1 for authentication to a LDAP
Distinguished Name (DN). You may need to use \fB\-\-ldapUserToDNMapping\f1\f1 to transform a
username into an LDAP DN in the following scenarios:
.RS
.IP \(bu 2
Performing LDAP authentication with simple LDAP binding, where users
authenticate to MongoDB with usernames that are not full LDAP DNs.
.IP \(bu 2
Using an \fBLDAP authorization query template\f1\f1 that requires a DN.
.IP \(bu 2
Transforming the usernames of clients authenticating to Mongo DB
using different authentication mechanisms, such as x.509 or
kerberos, to a full LDAP DN for authorization.
.RE
.PP
\fB\-\-ldapUserToDNMapping\f1\f1 expects a quote\-enclosed JSON\-string representing an ordered array
of documents. Each document contains a regular expression \fBmatch\f1 and
either a \fBsubstitution\f1 or \fBldapQuery\f1 template used for transforming the
incoming username.
.PP
Each document in the array has the following form:
.PP
.EX
  {
    match: "<regex>"
    substitution: "<LDAP DN>" | ldapQuery: "<LDAP Query>"
  }
.EE
.RS
.IP \(bu 2
.RS
.IP \(bu 4
Field
.IP \(bu 4
Description
.IP \(bu 4
Example
.RE
.IP \(bu 2
.RS
.IP \(bu 4
\fBmatch\f1
.IP \(bu 4
An ECMAScript\-formatted regular expression (regex) to match against a
provided username. Each parenthesis\-enclosed section represents a
regex capture group used by \fBsubstitution\f1 or \fBldapQuery\f1\&.
.IP \(bu 4
\fB"(.+)ENGINEERING"\f1
\fB"(.+)DBA"\f1
.RE
.IP \(bu 2
.RS
.IP \(bu 4
\fBsubstitution\f1
.IP \(bu 4
An LDAP distinguished name (DN) formatting template that converts the
authentication name matched by the \fBmatch\f1 regex into a LDAP DN.
Each curly bracket\-enclosed numeric value is replaced by the
corresponding regex capture group (http://www.regular\-expressions.info/refcapture.html) extracted
from the authentication username via the \fBmatch\f1 regex.
.IP
The result of the substitution must be an RFC4514 (https://www.ietf.org/rfc/rfc4514.txt) escaped string.
.IP \(bu 4
\fB"cn={0},ou=engineering,
dc=example,dc=com"\f1
.RE
.IP \(bu 2
.RS
.IP \(bu 4
\fBldapQuery\f1
.IP \(bu 4
A LDAP query formatting template that inserts the authentication
name matched by the \fBmatch\f1 regex into an LDAP query URI encoded
respecting RFC4515 and RFC4516. Each curly bracket\-enclosed numeric
value is replaced by the corresponding regex capture group (http://www.regular\-expressions.info/refcapture.html) extracted
from the authentication username via the \fBmatch\f1 expression.
\fBmongod\f1 executes the query against the LDAP server to retrieve
the LDAP DN for the authenticated user. \fBmongod\f1 requires
exactly one returned result for the transformation to be
successful, or \fBmongod\f1 skips this transformation.
.IP \(bu 4
\fB"ou=engineering,dc=example,
dc=com??one?(user={0})"\f1
.RE
.RE
.PP
An explanation of  RFC4514 (https://www.ietf.org/rfc/rfc4514.txt),
RFC4515 (https://tools.ietf.org/html/rfc4515),
RFC4516 (https://tools.ietf.org/html/rfc4516), or LDAP queries is out
of scope for the MongoDB Documentation. Please review the RFC directly or
use your preferred LDAP resource.
.PP
For each document in the array, you must use either \fBsubstitution\f1 or
\fBldapQuery\f1\&. You \fIcannot\f1 specify both in the same document.
.PP
When performing authentication or authorization, \fBmongod\f1 steps through
each document in the array in the given order, checking the authentication
username against the \fBmatch\f1 filter.  If a match is found,
\fBmongod\f1 applies the transformation and uses the output for
authenticating the user. \fBmongod\f1 does not check the remaining documents
in the array.
.PP
If the given document does not match the provided authentication
name, \fBmongod\f1 continues through the list of documents
to find additional matches. If no matches are found in any document,
or the transformation the document describes fails,
\fBmongod\f1 returns an error.
.PP
\fBmongod\f1 also returns an error if one of the transformations cannot be
evaluated due to networking or authentication failures to the LDAP server.
\fBmongod\f1 rejects the connection request and does not check the remaining
documents in the array.
.PP
Starting in MongoDB 5.0, \fB\-\-ldapUserToDNMapping\f1\f1
accepts an empty string \fB""\f1 or empty array \fB[ ]\f1 in place of a
mapping documnent. If providing an empty string or empty array to
\fB\-\-ldapUserToDNMapping\f1\f1, MongoDB maps the
authenticated username as the LDAP DN. In earlier versions, providing
an empty mapping document causes mapping to fail.
.PP
The following shows two transformation documents. The first
document matches against any string ending in \fB@ENGINEERING\f1, placing
anything preceeding the suffix into a regex capture group. The
second document matches against any string ending in \fB@DBA\f1, placing
anything preceeding the suffix into a regex capture group.
.PP
.EX
  "[
     {
        match: "(.+)@ENGINEERING.EXAMPLE.COM",
        substitution: "cn={0},ou=engineering,dc=example,dc=com"
     },
     {
        match: "(.+)@DBA.EXAMPLE.COM",
        ldapQuery: "ou=dba,dc=example,dc=com??one?(user={0})"
  
     }
  
  ]"
.EE
.PP
A user with username \fBalice@ENGINEERING.EXAMPLE.COM\f1 matches the first
document. The regex capture group \fB{0}\f1 corresponds to the string
\fBalice\f1\&. The resulting output is the DN
\fB"cn=alice,ou=engineering,dc=example,dc=com"\f1\&.
.PP
A user with username \fBbob@DBA.EXAMPLE.COM\f1 matches the second document.
The regex capture group \fB{0}\f1 corresponds to the string \fBbob\f1\&.  The
resulting output is the LDAP query
\fB"ou=dba,dc=example,dc=com??one?(user=bob)"\f1\&. \fBmongod\f1 executes this
query against the LDAP server, returning the result
\fB"cn=bob,ou=dba,dc=example,dc=com"\f1\&.
.PP
If \fB\-\-ldapUserToDNMapping\f1\f1 is unset, \fBmongod\f1 applies no transformations to the username
when attempting to authenticate or authorize a user against the LDAP server.
.PP
This setting can be configured on a running \fBmongod\f1 using the
\fBsetParameter\f1\f1 database command.
.RE
.PP
\fBmongod \-\-ldapAuthzQueryTemplate\f1
.RS
.PP
\fIAvailable in MongoDB Enterprise only.\f1
.PP
A relative LDAP query URL formatted conforming to RFC4515 (https://tools.ietf.org/html/rfc4515) and RFC4516 (https://tools.ietf.org/html/rfc4516) that \fBmongod\f1 executes to obtain
the LDAP groups to which the authenticated user belongs to. The query is
relative to the host or hosts specified in \fB\-\-ldapServers\f1\f1\&.
.PP
In the URL, you can use the following substituion tokens:
.RS
.IP \(bu 2
.RS
.IP \(bu 4
Substitution Token
.IP \(bu 4
Description
.RE
.IP \(bu 2
.RS
.IP \(bu 4
\fB{USER}\f1
.IP \(bu 4
Substitutes the authenticated username, or the
\fBtransformed\f1\f1
username if a \fBusername mapping\f1\f1 is specified.
.RE
.IP \(bu 2
.RS
.IP \(bu 4
\fB{PROVIDED_USER}\f1
.IP \(bu 4
Substitutes the supplied username, i.e. before either
authentication or \fBLDAP transformation\f1\f1\&.
.RE
.RE
.PP
When constructing the query URL, ensure that the order of LDAP parameters
respects RFC4516:
.PP
.EX
  [ dn  [ ? [attributes] [ ? [scope] [ ? [filter] [ ? [Extensions] ] ] ] ] ]
.EE
.PP
If your query includes an attribute, \fBmongod\f1 assumes that the query
retrieves a the DNs which this entity is member of.
.PP
If your query does not include an attribute, \fBmongod\f1 assumes
the query retrieves all entities which the user is member of.
.PP
For each LDAP DN returned by the query, \fBmongod\f1 assigns the authorized
user a corresponding role on the \fBadmin\f1 database. If a role on the on the
\fBadmin\f1 database exactly matches the DN, \fBmongod\f1 grants the user the
roles and privileges assigned to that role. See the
\fBdb.createRole()\f1\f1 method for more information on creating roles.
.PP
This LDAP query returns any groups listed in the LDAP user object\(aqs
\fBmemberOf\f1 attribute.
.PP
.EX
  "{USER}?memberOf?base"
.EE
.PP
Your LDAP configuration may not include the \fBmemberOf\f1 attribute as part
of the user schema, may possess a different attribute for reporting group
membership, or may not track group membership through attributes.
Configure your query with respect to your own unique LDAP configuration.
.PP
If unset, \fBmongod\f1 cannot authorize users using LDAP.
.PP
This setting can be configured on a running \fBmongod\f1 using the
\fBsetParameter\f1\f1 database command.
.PP
An explanation of RFC4515 (https://tools.ietf.org/html/rfc4515),
RFC4516 (https://tools.ietf.org/html/rfc4516) or LDAP queries is out
of scope for the MongoDB Documentation. Please review the RFC directly or
use your preferred LDAP resource.
.RE
.SS STORAGE OPTIONS
.PP
\fBmongod \-\-storageEngine\f1
.RS
.PP
\fIDefault\f1: \fBwiredTiger\f1
.PP
Specifies the storage engine for the \fBmongod\f1 database. Available
values include:
.RS
.IP \(bu 2
.RS
.IP \(bu 4
Value
.IP \(bu 4
Description
.RE
.IP \(bu 2
.RS
.IP \(bu 4
\fBwiredTiger\f1
.IP \(bu 4
To specify the \fBWiredTiger Storage Engine\f1\&.
.RE
.IP \(bu 2
.RS
.IP \(bu 4
\fBinMemory\f1
.IP \(bu 4
To specify the \fBIn\-Memory Storage Engine\f1\&.
.IP
\fIAvailable in MongoDB Enterprise only.\f1
.RE
.RE
.PP
If you attempt to start a \fBmongod\f1 with a
\fB\-\-dbpath\f1\f1 that contains data files produced by a
storage engine other than the one specified by
\fB\-\-storageEngine\f1\f1, \fBmongod\f1 doesn\(aqt start.
.RE
.PP
\fBmongod \-\-dbpath\f1
.RS
.PP
\fIDefault\f1: \fB/data/db\f1 on Linux and macOS, \fB\data\db\f1 on Windows
.PP
The directory where the \fBmongod\f1 instance stores its data.
.PP
If using the default
\fBConfiguration File\f1
included with a package manager installation of MongoDB, the
corresponding \fBstorage.dbPath\f1\f1 setting uses a different
default.
.PP
The files in \fB\-\-dbpath\f1\f1 must correspond to the storage engine
specified in \fB\-\-storageEngine\f1\f1\&. If the data files do not
correspond to \fB\-\-storageEngine\f1\f1, \fBmongod\f1 doesn\(aqt start.
.RE
.PP
\fBmongod \-\-directoryperdb\f1
.RS
.PP
Uses a separate directory to store data for each database. The
directories are under the \fB\-\-dbpath\f1\f1 directory, and each subdirectory
name corresponds to the database name.
.PP
Not available for \fBmongod\f1\f1 instances that use the
\fBin\-memory storage engine\f1\&.
.PP
Starting in MongoDB 5.0, dropping the final collection in a database
(or dropping the database itself) when \fB\-\-directoryperdb\f1\f1 is
enabled deletes the newly empty subdirectory for that database.
.PP
To change the \fB\-\-directoryperdb\f1\f1 option for existing
deployments:
.RS
.IP \(bu 2
For standalone instances:
.RS
.IP \(bu 4
Use \fBmongodump\f1\f1 on the existing
\fBmongod\f1 instance to generate a backup.
.IP \(bu 4
Stop the \fBmongod\f1 instance.
.IP \(bu 4
Add the \fB\-\-directoryperdb\f1\f1 value \fBand\f1
configure a new data directory
.IP \(bu 4
Restart the \fBmongod\f1 instance.
.IP \(bu 4
Use \fBmongorestore\f1\f1 to populate the new data
directory.
.RE
.IP \(bu 2
For replica sets:
.RS
.IP \(bu 4
Stop a secondary member.
.IP \(bu 4
Add the \fB\-\-directoryperdb\f1\f1 value \fBand\f1
configure a new data directory to that secondary member.
.IP \(bu 4
Restart that secondary.
.IP \(bu 4
Use \fBinitial sync\f1 to populate
the new data directory.
.IP \(bu 4
Update remaining secondaries in the same fashion.
.IP \(bu 4
Step down the primary, and update the stepped\-down member in the
same fashion.
.RE
.RE
.RE
.PP
\fBmongod \-\-syncdelay\f1
.RS
.PP
\fIDefault\f1: 60
.PP
Controls how much time can pass before MongoDB flushes data to the data
files.
.PP
\fBDo not set this value on
production systems.\f1 In almost every situation, you should use the
default setting.
.PP
The \fBmongod\f1 process writes data very quickly to the journal and
lazily to the data files. \fB\-\-syncdelay\f1\f1 has no effect on
\fBjournaling\f1, but if \fB\-\-syncdelay\f1\f1 is set to
\fB0\f1 the journal eventually consumes all available disk space.
.PP
Not available for \fBmongod\f1\f1 instances that use the
\fBin\-memory storage engine\f1\&.
.PP
To provide \fBdurable\f1 data, \fBWiredTiger\f1
uses \fBcheckpoints\f1\&. For more
details, see \fBJournaling and the WiredTiger Storage Engine\f1\&.
.RE
.PP
\fBmongod \-\-upgrade\f1
.RS
.PP
Upgrades the on\-disk data format of the files specified by the
\fB\-\-dbpath\f1\f1 to the latest version, if needed.
.PP
This option only affects the operation of the \fBmongod\f1 if the data
files are in an old format.
.PP
In most cases you should not set this value, so you can exercise the
most control over your upgrade process. See the MongoDB release notes
for more information about the upgrade process.
.RE
.PP
\fBmongod \-\-repair\f1
.RS
.PP
Runs a repair routine on all databases for a \fBmongod\f1
instance.
.PP
Starting in MongoDB 5.0:
.RS
.IP \(bu 2
The repair operation validates the collections to find any
inconsistencies and fixes them if possible, which avoids
rebuilding the indexes.
.IP \(bu 2
If a collection\(aqs data file is salvaged or if the collection has
inconsistencies that the validate step is unable to fix, then all
indexes are rebuilt.
.RE
.PP
If you are running with \fBjournaling\f1 enabled, there is
almost never any need to run repair since the server can use the
journal files to restore the data files to a clean state automatically.
However, you may need to run repair in cases where you need to recover
from a disk\-level data corruption.
.RS
.IP \(bu 2
Only use \fBmongod \-\-repair\f1\f1 if you have no other options.
The operation removes and does not save any corrupt data during
the repair process.
.IP \(bu 2
Avoid running \fB\-\-repair\f1\f1 against
a replica set member:
.RS
.IP \(bu 4
To repair a \fBreplica set\f1 member, if you have an intact
copy of your data available (e.g. a recent backup or an intact
member of the \fBreplica set\f1), restore from that intact
copy instead. To learn more, see \fBResync a Member of a Replica Set\f1\&.
.IP \(bu 4
If you choose to run \fBmongod \-\-repair\f1\f1 against a
replica set member and the operation modifies the data or the
metadata, you must still perform a full resync in order for the
member to rejoin the replica set.
.RE
.IP \(bu 2
Before using \fB\-\-repair\f1\f1, make a backup
copy of the \fBdbpath\f1\f1 directory.
.IP \(bu 2
If repair fails to complete for any reason, you must restart the
instance using the \fB\-\-repair\f1\f1 option.
.RE
.RE
.PP
\fBmongod \-\-journalCommitInterval\f1
.RS
.PP
\fIDefault\f1: 100
.PP
The maximum amount of time in milliseconds that
the \fBmongod\f1 process allows between
journal operations. Values can range from 1 to 500 milliseconds. Lower
values increase the durability of the journal, at the expense of disk
performance.
.PP
On WiredTiger, the default journal commit interval is 100
milliseconds. A write that includes or implies
\fBj:true\f1 causes an immediate sync of the journal. For details
and additional conditions that affect the frequency of the sync, see
\fBJournaling Process\f1\&.
.PP
Not available for \fBmongod\f1\f1 instances that use the
\fBin\-memory storage engine\f1\&.
.RE
.SS WIREDTIGER OPTIONS
.PP
\fBmongod \-\-wiredTigerCacheSizeGB\f1
.RS
.PP
Defines the maximum size of the internal cache that WiredTiger
uses for all data. The memory consumed by an index build (see
\fBmaxIndexBuildMemoryUsageMegabytes\f1\f1) is separate from the
WiredTiger cache memory.
.PP
Values can range from \fB0.25\f1 GB to \fB10000\f1 GB.
.PP
The default WiredTiger internal cache size is the larger of either:
.RS
.IP \(bu 2
50% of (RAM \- 1 GB), or
.IP \(bu 2
256 MB.
.RE
.PP
For example, on a system with a total of 4GB of RAM the
WiredTiger cache uses 1.5GB of RAM (\fB0.5 * (4 GB \- 1 GB) =
1.5 GB\f1). Conversely, on a system with a total of 1.25 GB of
RAM WiredTiger allocates 256 MB to the WiredTiger cache
because that is more than half of the total RAM minus one
gigabyte (\fB0.5 * (1.25 GB \- 1 GB) = 128 MB < 256 MB\f1).
.PP
In some instances, such as when running in a container, the database
can have memory constraints that are lower than the total system
memory. In such instances, this memory limit, rather than the total
system memory, is used as the maximum RAM available.
.PP
To see the memory limit, see \fBhostInfo.system.memLimitMB\f1\f1\&.
.PP
Avoid increasing the WiredTiger internal cache size above its
default value.
.PP
With WiredTiger, MongoDB utilizes both the WiredTiger internal cache
and the filesystem cache.
.PP
With the filesystem cache, MongoDB automatically uses all free memory
that is not used by the WiredTiger cache or by other processes.
.PP
The \fB\-\-wiredTigerCacheSizeGB\f1\f1 limits the size of the WiredTiger internal
cache. The operating system uses the available free memory
for filesystem cache, which allows the compressed MongoDB data
files to stay in memory. In addition, the operating system
uses any free RAM to buffer file system blocks and file system
cache.
.PP
To accommodate the additional consumers of RAM, you may have to
decrease WiredTiger internal cache size.
.PP
The default WiredTiger internal cache size value assumes that there is a
single \fBmongod\f1\f1 instance per machine. If a single machine
contains multiple MongoDB instances, then you should decrease the setting to
accommodate the other \fBmongod\f1\f1
instances.
.PP
If you run \fBmongod\f1\f1 in a container (for example, \fBlxc\f1,
\fBcgroups\f1, Docker, etc.) that does \fInot\f1 have access to all of the
RAM available in a system, you must set \fB\-\-wiredTigerCacheSizeGB\f1\f1 to a value
less than the amount of RAM available in the container. The exact
amount depends on the other processes running in the container. See
\fBmemLimitMB\f1\f1\&.
.RE
.PP
\fBmongod \-\-wiredTigerJournalCompressor\f1
.RS
.PP
\fIDefault\f1: snappy
.PP
Specifies the type of compression to use to compress WiredTiger
journal data.
.PP
Available compressors are:
.RS
.IP \(bu 2
\fBnone\f1
.IP \(bu 2
\fBsnappy\f1
.IP \(bu 2
\fBzlib\f1
.IP \(bu 2
\fBzstd\f1
.RE
.RE
.PP
\fBmongod \-\-wiredTigerDirectoryForIndexes\f1
.RS
.PP
When you start \fBmongod\f1 with \fB\-\-wiredTigerDirectoryForIndexes\f1\f1, \fBmongod\f1 stores indexes and collections in separate
subdirectories under the data (i.e. \fB\-\-dbpath\f1\f1) directory.
Specifically, \fBmongod\f1 stores the indexes in a subdirectory named
\fBindex\f1 and the collection data in a subdirectory named
\fBcollection\f1\&.
.PP
By using a symbolic link, you can specify a different location for
the indexes. Specifically, when \fBmongod\f1 instance is \fBnot\f1
running, move the \fBindex\f1 subdirectory to the destination and
create a symbolic link named \fBindex\f1 under the data directory to
the new destination.
.RE
.PP
\fBmongod \-\-wiredTigerCollectionBlockCompressor\f1
.RS
.PP
\fIDefault\f1: snappy
.PP
Specifies the default compression for collection data. You can
override this on a per\-collection basis when creating collections.
.PP
Available compressors are:
.RS
.IP \(bu 2
\fBnone\f1
.IP \(bu 2
\fBsnappy\f1
.IP \(bu 2
\fBzlib\f1
.IP \(bu 2
\fBzstd\f1
.RE
.PP
\fB\-\-wiredTigerCollectionBlockCompressor\f1\f1 affects all collections created. If you change
the value of \fB\-\-wiredTigerCollectionBlockCompressor\f1\f1 on an existing MongoDB deployment, all new
collections use the specified compressor. Existing collections
continue to use the compressor specified when they were
created, or the default compressor at that time.
.RE
.PP
\fBmongod \-\-wiredTigerIndexPrefixCompression\f1
.RS
.PP
\fIDefault\f1: true
.PP
Enables or disables \fBprefix compression\f1 for index data.
.PP
Specify \fBtrue\f1 for \fB\-\-wiredTigerIndexPrefixCompression\f1\f1 to enable \fBprefix compression\f1 for
index data, or \fBfalse\f1 to disable prefix compression for index data.
.PP
The \fB\-\-wiredTigerIndexPrefixCompression\f1\f1 setting affects all indexes created. If you change
the value of \fB\-\-wiredTigerIndexPrefixCompression\f1\f1 on an existing MongoDB deployment, all new
indexes use prefix compression. Existing indexes
are not affected.
.RE
.SS REPLICATION OPTIONS
.PP
\fBmongod \-\-replSet\f1
.RS
.PP
Configures replication. Specify a replica set name as an argument to
this set. All hosts in the replica set must have the same set name.
.PP
If your application connects to more than one replica set, each set must
have a distinct name. Some drivers group replica set connections by
replica set name.
.RE
.PP
\fBmongod \-\-oplogSize\f1
.RS
.PP
The maximum size in megabytes for the \fBoplog\f1\&. The
\fBoplogSize\f1 setting configures the uncompressed size of the
oplog, not the size on disk.
.PP
The oplog can grow past its configured size
limit to avoid deleting the \fBmajority commit point\f1\f1\&.
.PP
By default, the \fBmongod\f1 process creates an \fBoplog\f1 based on
the maximum amount of space available. For 64\-bit systems, the oplog
is typically 5% of available disk space.
.PP
Once the \fBmongod\f1 has created the oplog for the first time,
changing the \fB\-\-oplogSize\f1\f1 option doesn\(aqt affect the size of
the oplog. To change the minimum oplog retention period after
starting the \fBmongod\f1, use
\fBreplSetResizeOplog\f1\f1\&. \fBreplSetResizeOplog\f1\f1
enables you to resize the oplog dynamically without restarting the
\fBmongod\f1 process. To persist the changes made using
\fBreplSetResizeOplog\f1\f1 through a restart, update the value
of \fB\-\-oplogSize\f1\f1\&.
.PP
See \fBOplog Size\f1 for more information.
.RE
.PP
\fBmongod \-\-oplogMinRetentionHours\f1
.RS
.PP
Specifies the minimum number of hours to preserve an oplog entry,
where the decimal values represent the fractions of an hour. For
example, a value of \fB1.5\f1 represents one hour and thirty
minutes.
.PP
The value must be greater than or equal to \fB0\f1\&. A value of \fB0\f1
indicates that the \fBmongod\f1 should truncate the oplog
starting with the oldest entries to maintain the configured
maximum oplog size.
.PP
Defaults to \fB0\f1\&.
.PP
A \fBmongod\f1 started with \fB\-\-oplogMinRetentionHours\f1
only removes an oplog entry \fIif\f1:
.RS
.IP \(bu 2
The oplog has reached the maximum configured oplog size \fIand\f1
.IP \(bu 2
The oplog entry is older than the configured number of hours based
on the host system clock.
.RE
.PP
The \fBmongod\f1 has the following behavior when configured
with a minimum oplog retention period:
.RS
.IP \(bu 2
The oplog can grow without constraint so as to retain oplog entries
for the configured number of hours. This may result in reduction or
exhaustion of system disk space due to a combination of high write
volume and large retention period.
.IP \(bu 2
If the oplog grows beyond its maximum size, the
\fBmongod\f1 may continue to hold that disk space even if
the oplog returns to its maximum size \fIor\f1 is configured for a
smaller maximum size. See \fBReducing Oplog Size Does Not Immediately Return Disk Space\f1\&.
.IP \(bu 2
The \fBmongod\f1 compares the system wall clock to an
oplog entries creation wall clock time when enforcing oplog entry
retention. Clock drift between cluster components may result in
unexpected oplog retention behavior. See
\fBClock Synchronization\f1 for more information on
clock synchronization across cluster members.
.RE
.PP
To change the minimum oplog retention period after starting the
\fBmongod\f1, use \fBreplSetResizeOplog\f1\f1\&.
\fBreplSetResizeOplog\f1\f1 enables you to resize the oplog
dynamically without restarting the \fBmongod\f1 process. To
persist the changes made using \fBreplSetResizeOplog\f1\f1
through a restart, update the value of
\fB\-\-oplogMinRetentionHours\f1\f1\&.
.RE
.PP
If you are using a three\-member primary\-secondary\-arbiter (PSA)
architecture, consider the following:
.RS
.IP \(bu 2
The write concern \fB"majority"\f1\f1 can cause
performance issues if a secondary is unavailable or lagging. For
advice on how to mitigate these issues, see
\fBMitigate Performance Issues with PSA Replica Set\f1\&.
.IP \(bu 2
If you are using a global default \fB"majority"\f1\f1
and the write concern is less than the size of the majority,
your queries may return stale (not fully replicated) data.
.RE
.RE
.SS SHARDED CLUSTER OPTIONS
.PP
\fBmongod \-\-configsvr\f1
.RS
.PP
\fIRequired if starting a config server.\f1
.PP
Declares that this \fBmongod\f1 instance serves as the \fBconfig
server\f1 of a sharded cluster. When
running with this option, clients (i.e. other cluster components)
cannot write data to any database other than \fBconfig\f1
and \fBadmin\f1\&. The default port for a \fBmongod\f1 with this option is
\fB27019\f1 and the default \fB\-\-dbpath\f1\f1 directory is
\fB/data/configdb\f1, unless specified.
.PP
When starting a MongoDB server with \fB\-\-configsvr\f1, you must also
specify a \fB\-\-replSet\f1\f1\&.
.PP
The use of the deprecated mirrored \fBmongod\f1 instances as
config servers (SCCC) is no longer supported.
.PP
The replica set config servers (CSRS) must run the
\fBWiredTiger storage engine\f1\&.
.PP
The \fB\-\-configsvr\f1\f1 option creates a local \fBoplog\f1\&.
.PP
Do not use the \fB\-\-configsvr\f1\f1 option with \fB\-\-shardsvr\f1\f1\&. Config
servers cannot be a shard server.
.PP
Do not use the \fB\-\-configsvr\f1\f1 with the
\fBskipShardingConfigurationChecks\f1\f1 parameter. That is, if
you are temporarily starting the \fBmongod\f1 as a
standalone for maintenance operations, include the parameter
\fBskipShardingConfigurationChecks\f1\f1 and exclude \fB\-\-configsvr\f1\f1\&.
Once maintenance has completed, remove the
\fBskipShardingConfigurationChecks\f1\f1 parameter and restart
with \fB\-\-configsvr\f1\f1\&.
.RE
.PP
\fBmongod \-\-shardsvr\f1
.RS
.PP
\fIRequired if starting a shard server.\f1
.PP
Configures this \fBmongod\f1 instance as a shard in a
sharded cluster. The default port for these instances is
\fB27018\f1\&.
.PP
When starting a MongoDB server with \fB\-\-shardsvr\f1, you must also
specify a \fB\-\-replSet\f1\f1\&.
.PP
Do not use the \fB\-\-shardsvr\f1\f1 with the
\fBskipShardingConfigurationChecks\f1\f1 parameter. That is, if
you are temporarily starting the \fBmongod\f1 as a
standalone for maintenance operations, include the parameter
\fBskipShardingConfigurationChecks\f1\f1 and exclude \fB\-\-shardsvr\f1\f1\&.
Once maintenance has completed, remove the
\fBskipShardingConfigurationChecks\f1\f1 parameter and restart
with \fB\-\-shardsvr\f1\f1\&.
.RE
.SS TLS OPTIONS
.PP
\fBConfigure mongod\f1 and mongos\f1 for TLS/SSL\f1 for full
documentation of MongoDB\(aqs support.
.PP
\fBmongod \-\-tlsMode\f1
.RS
.PP
Enables TLS used for all network connections. The
argument to the \fB\-\-tlsMode\f1\f1 option can be one of the following:
.RS
.IP \(bu 2
.RS
.IP \(bu 4
Value
.IP \(bu 4
Description
.RE
.IP \(bu 2
.RS
.IP \(bu 4
\fBdisabled\f1
.IP \(bu 4
The server does not use TLS.
.RE
.IP \(bu 2
.RS
.IP \(bu 4
\fBallowTLS\f1
.IP \(bu 4
Connections between servers do not use TLS. For incoming
connections, the server accepts both TLS and non\-TLS.
.RE
.IP \(bu 2
.RS
.IP \(bu 4
\fBpreferTLS\f1
.IP \(bu 4
Connections between servers use TLS. For incoming
connections, the server accepts both TLS and non\-TLS.
.RE
.IP \(bu 2
.RS
.IP \(bu 4
\fBrequireTLS\f1
.IP \(bu 4
The server uses and accepts only TLS encrypted connections.
.RE
.RE
.PP
If \fB\-\-tlsCAFile\f1 or \fBtls.CAFile\f1 is not
specified and you are not using x.509 authentication, you must set the
\fBtlsUseSystemCA\f1\f1 parameter to \fBtrue\f1\&. This makes MongoDB use
the system\-wide CA certificate store when connecting to a TLS\-enabled server.
.PP
If using x.509 authentication, \fB\-\-tlsCAFile\f1 or \fBtls.CAFile\f1
must be specified unless using \fB\-\-tlsCertificateSelector\f1\f1\&.
.PP
For more information about TLS and MongoDB, see
\fBConfigure mongod\f1 and mongos\f1 for TLS/SSL\f1 and
\fBTLS/SSL Configuration for Clients\f1 .
.RE
.PP
\fBmongod \-\-tlsCertificateKeyFile\f1
.RS
.PP
Specifies the \&.pem file that contains both the TLS certificate and
key.
.PP
On macOS or Windows, you can use the
\fB\-\-tlsCertificateSelector\f1\f1 option to specify a
certificate from the operating system\(aqs secure certificate store
instead of a PEM key file. \fB\-\-tlsCertificateKeyFile\f1\f1 and
\fB\-\-tlsCertificateSelector\f1\f1 options are mutually exclusive.
You can only specify one.
.RS
.IP \(bu 2
On Linux/BSD, you must specify \fB\-\-tlsCertificateKeyFile\f1\f1
when TLS/SSL is enabled.
.IP \(bu 2
On Windows or macOS, you must specify either
\fB\-\-tlsCertificateKeyFile\f1\f1 or
\fB\-\-tlsCertificateSelector\f1\f1 when TLS/SSL is enabled.
.IP
For Windows \fBonly\f1, MongoDB does not support
encrypted PEM files. The \fBmongod\f1 fails to start if
it encounters an encrypted PEM file. To securely store and
access a certificate for use with TLS on Windows,
use \fB\-\-tlsCertificateSelector\f1\f1\&.
.RE
.PP
For more information about TLS and MongoDB, see
\fBConfigure mongod\f1 and mongos\f1 for TLS/SSL\f1 and
\fBTLS/SSL Configuration for Clients\f1 .
.RE
.PP
\fBmongod \-\-tlsCertificateKeyFilePassword\f1
.RS
.PP
Specifies the password to decrypt the certificate\-key file (i.e.
\fB\-\-tlsCertificateKeyFile\f1\f1). Use the
\fB\-\-tlsCertificateKeyFilePassword\f1\f1 option only if the
certificate\-key file is encrypted. In all cases, the
\fBmongod\f1 redacts the password from all logging and
reporting output.
.RS
.IP \(bu 2
On Linux/BSD, if the private key in the PEM file is encrypted and
you do not specify the \fB\-\-tlsCertificateKeyFilePassword\f1\f1 option, MongoDB prompts for a
passphrase. See \fBTLS/SSL Certificate Passphrase\f1\&.
.IP \(bu 2
On macOS, if the private key in the PEM file is
encrypted, you must explicitly specify the
\fB\-\-tlsCertificateKeyFilePassword\f1\f1 option. Alternatively,
you can use a certificate from the secure system store (see
\fB\-\-tlsCertificateSelector\f1\f1) instead of a PEM file or use an
unencrypted PEM file.
.IP \(bu 2
On Windows, MongoDB does not support encrypted certificates.
The \fBmongod\f1 fails if it encounters an encrypted
PEM file. Use \fB\-\-tlsCertificateSelector\f1\f1 instead.
.RE
.PP
For more information about TLS and MongoDB, see
\fBConfigure mongod\f1 and mongos\f1 for TLS/SSL\f1 and
\fBTLS/SSL Configuration for Clients\f1 .
.RE
.PP
\fBmongod \-\-clusterAuthMode\f1
.RS
.PP
\fIDefault\f1: keyFile
.PP
The authentication mode used for cluster authentication. If you use
\fBinternal x.509 authentication\f1,
specify so here. This option can have one of the following values:
.RS
.IP \(bu 2
.RS
.IP \(bu 4
Value
.IP \(bu 4
Description
.RE
.IP \(bu 2
.RS
.IP \(bu 4
\fBkeyFile\f1
.IP \(bu 4
Use a keyfile for authentication.
Accept only keyfiles.
.RE
.IP \(bu 2
.RS
.IP \(bu 4
\fBsendKeyFile\f1
.IP \(bu 4
For rolling upgrade purposes. Send a keyfile for
authentication but can accept both keyfiles and x.509
certificates.
.RE
.IP \(bu 2
.RS
.IP \(bu 4
\fBsendX509\f1
.IP \(bu 4
For rolling upgrade purposes. Send the x.509 certificate for
authentication but can accept both keyfiles and x.509
certificates.
.RE
.IP \(bu 2
.RS
.IP \(bu 4
\fBx509\f1
.IP \(bu 4
Recommended. Send the x.509 certificate for authentication and
accept only x.509 certificates.
.RE
.RE
.PP
If \fB\-\-tlsCAFile\f1 or \fBtls.CAFile\f1 is not
specified and you are not using x.509 authentication, you must set the
\fBtlsUseSystemCA\f1\f1 parameter to \fBtrue\f1\&. This makes MongoDB use
the system\-wide CA certificate store when connecting to a TLS\-enabled server.
.PP
If using x.509 authentication, \fB\-\-tlsCAFile\f1 or \fBtls.CAFile\f1
must be specified unless using \fB\-\-tlsCertificateSelector\f1\f1\&.
.PP
For more information about TLS and MongoDB, see
\fBConfigure mongod\f1 and mongos\f1 for TLS/SSL\f1 and
\fBTLS/SSL Configuration for Clients\f1 .
.RE
.PP
\fBmongod \-\-tlsClusterFile\f1
.RS
.PP
Specifies the \&.pem file that contains the x.509
certificate\-key file for \fBmembership authentication\f1 for the cluster or replica set.
.PP
On macOS or Windows, you can use the
\fB\-\-tlsClusterCertificateSelector\f1\f1 option to specify a
certificate from the operating system\(aqs secure certificate store
instead of a PEM key file. \fB\-\-tlsClusterFile\f1\f1 and
\fB\-\-tlsClusterCertificateSelector\f1\f1 options are mutually
exclusive. You can only specify one.
.PP
If \fB\-\-tlsClusterFile\f1\f1 does not specify the \fB\&.pem\f1 file for
internal cluster authentication or the alternative
\fB\-\-tlsClusterCertificateSelector\f1\f1, the cluster uses the
\fB\&.pem\f1 file specified in the \fB\-\-tlsCertificateKeyFile\f1\f1
option or the certificate returned by the
\fB\-\-tlsCertificateSelector\f1\f1\&.
.PP
If using x.509 authentication, \fB\-\-tlsCAFile\f1 or \fBtls.CAFile\f1
must be specified unless using \fB\-\-tlsCertificateSelector\f1\f1\&.
.PP
\fBmongod\f1\f1 / \fBmongos\f1\f1 logs a warning on
connection if the presented x.509 certificate expires within \fB30\f1
days of the \fBmongod/mongos\f1 host system time. See
\fBx.509 Certificates Nearing Expiry Trigger Warnings\f1 for more
information.
.PP
For more information about TLS and MongoDB, see
\fBConfigure mongod\f1 and mongos\f1 for TLS/SSL\f1 and
\fBTLS/SSL Configuration for Clients\f1 .
.PP
For Windows \fBonly\f1, MongoDB does not support
encrypted PEM files. The \fBmongod\f1 fails to start if
it encounters an encrypted PEM file. To securely store and
access a certificate for use with membership authentication on
Windows, use \fB\-\-tlsClusterCertificateSelector\f1\f1\&.
.RE
.PP
\fBmongod \-\-tlsCertificateSelector\f1
.RS
.PP
Available on Windows and macOS as an alternative to
\fB\-\-tlsCertificateKeyFile\f1\f1\&.
.PP
Specifies a certificate property in order to select a matching
certificate from the operating system\(aqs certificate store to use for
TLS.
.PP
The \fB\-\-tlsCertificateKeyFile\f1\f1 and
\fB\-\-tlsCertificateSelector\f1\f1 options are mutually exclusive.
You can only specify one.
.PP
\fB\-\-tlsCertificateSelector\f1\f1 accepts an argument of the format
\fB<property>=<value>\f1 where the property can be one of the
following:
.RS
.IP \(bu 2
.RS
.IP \(bu 4
Property
.IP \(bu 4
Value type
.IP \(bu 4
Description
.RE
.IP \(bu 2
.RS
.IP \(bu 4
\fBsubject\f1
.IP \(bu 4
ASCII string
.IP \(bu 4
Subject name or common name on certificate
.RE
.IP \(bu 2
.RS
.IP \(bu 4
\fBthumbprint\f1
.IP \(bu 4
hex string
.IP \(bu 4
A sequence of bytes, expressed as hexadecimal, used to
identify a public key by its SHA\-1 digest.
.IP
The \fBthumbprint\f1 is sometimes referred to as a
\fBfingerprint\f1\&.
.RE
.RE
.PP
When using the system SSL certificate store, OCSP (Online
Certificate Status Protocol) is used to validate the revocation
status of certificates.
.PP
The \fBmongod\f1 searches the operating system\(aqs secure
certificate store for the CA certificates required to validate the
full certificate chain of the specified TLS certificate.
Specifically, the secure certificate store must contain the root CA
and any intermediate CA certificates required to build the full
certificate chain to the TLS certificate. Do \fBnot\f1 use
\fB\-\-tlsCAFile\f1\f1 or \fB\-\-tlsClusterCAFile\f1\f1 to specify the
root and intermediate CA certificate
.PP
For example, if the TLS/SSL certificate was signed with a single root
CA certificate, the secure certificate store must contain that root
CA certificate. If the TLS/SSL certificate was signed with an
intermediate CA certificate, the secure certificate store must
contain the intermedia CA certificate \fIand\f1 the root CA certificate.
.PP
You cannot use the \fBrotateCertificates\f1\f1 command or the
\fBdb.rotateCertificates()\f1\f1 shell method when using
\fBnet.tls.certificateSelector\f1\f1 or
\fB\-\-tlsCertificateSelector\f1\f1
set to \fBthumbprint\f1
.RE
.PP
\fBmongod \-\-tlsClusterCertificateSelector\f1
.RS
.PP
Available on Windows and macOS as an alternative to
\fB\-\-tlsClusterFile\f1\f1\&.
.PP
Specifies a certificate property in order to select a matching
certificate from the operating system\(aqs certificate store
for \fBinternal x.509 membership authentication\f1\&.
.PP
\fB\-\-tlsClusterFile\f1\f1 and
\fB\-\-tlsClusterCertificateSelector\f1\f1 options are mutually
exclusive. You can only specify one.
.PP
\fB\-\-tlsClusterCertificateSelector\f1\f1 accepts an argument of the
format \fB<property>=<value>\f1 where the property can be one of the
following:
.RS
.IP \(bu 2
.RS
.IP \(bu 4
Property
.IP \(bu 4
Value type
.IP \(bu 4
Description
.RE
.IP \(bu 2
.RS
.IP \(bu 4
\fBsubject\f1
.IP \(bu 4
ASCII string
.IP \(bu 4
Subject name or common name on certificate
.RE
.IP \(bu 2
.RS
.IP \(bu 4
\fBthumbprint\f1
.IP \(bu 4
hex string
.IP \(bu 4
A sequence of bytes, expressed as hexadecimal, used to
identify a public key by its SHA\-1 digest.
.IP
The \fBthumbprint\f1 is sometimes referred to as a
\fBfingerprint\f1\&.
.RE
.RE
.PP
The \fBmongod\f1 searches the operating system\(aqs secure
certificate store for the CA certificates required to validate the
full certificate chain of the specified cluster certificate.
Specifically, the secure certificate store must contain the root CA
and any intermediate CA certificates required to build the full
certificate chain to the cluster certificate. Do \fBnot\f1 use
\fB\-\-tlsCAFile\f1\f1 or \fB\-\-tlsClusterCAFile\f1\f1 to specify the
root and intermediate CA certificate.
.PP
For example, if the cluster certificate was signed with a single root
CA certificate, the secure certificate store must contain that root
CA certificate. If the cluster certificate was signed with an
intermediate CA certificate, the secure certificate store must
contain the intermedia CA certificate \fIand\f1 the root CA certificate.
.PP
\fBmongod\f1\f1 / \fBmongos\f1\f1 logs a warning on
connection if the presented x.509 certificate expires within \fB30\f1
days of the \fBmongod/mongos\f1 host system time. See
\fBx.509 Certificates Nearing Expiry Trigger Warnings\f1 for more
information.
.RE
.PP
\fBmongod \-\-tlsClusterPassword\f1
.RS
.PP
Specifies the password to decrypt the x.509 certificate\-key file
specified with \fB\-\-tlsClusterFile\f1\f1\&. Use the
\fB\-\-tlsClusterPassword\f1\f1 option only if the certificate\-key
file is encrypted. In all cases, the \fBmongod\f1 redacts
the password from all logging and reporting output.
.RS
.IP \(bu 2
On Linux/BSD, if the private key in the x.509 file is encrypted and
you do not specify the \fB\-\-tlsClusterPassword\f1\f1 option,
MongoDB prompts for a passphrase. See
\fBTLS/SSL Certificate Passphrase\f1\&.
.IP \(bu 2
On macOS, if the private key in the x.509 file is
encrypted, you must explicitly specify the
\fB\-\-tlsClusterPassword\f1\f1 option. Alternatively, you can
either use a certificate from the secure system store (see
\fB\-\-tlsClusterCertificateSelector\f1\f1) instead of a cluster PEM
file or use an unencrypted PEM file.
.IP \(bu 2
On Windows, MongoDB does not support encrypted certificates.
The \fBmongod\f1 fails if it encounters an encrypted
PEM file. Use \fB\-\-tlsClusterCertificateSelector\f1\f1 instead.
.RE
.PP
For more information about TLS and MongoDB, see
\fBConfigure mongod\f1 and mongos\f1 for TLS/SSL\f1 and
\fBTLS/SSL Configuration for Clients\f1 .
.RE
.PP
\fBmongod \-\-tlsCAFile\f1
.RS
.PP
Specifies the \&.pem file that contains the root certificate
chain from the Certificate Authority. Specify the file name of the
\&.pem file using relative or absolute paths.
.PP
When starting a \fBmongod\f1\f1 instance with
\fBTLS/SSL enabled\f1, you must
specify a value for the \fB\-\-tlsCAFile\f1\f1 flag, the
\fBnet.tls.CAFile\f1\f1 configuration option, or the \fBtlsUseSystemCA\f1\f1
parameter.
.PP
\fB\-\-tlsCAFile\f1, \fBtls.CAFile\f1, and \fBtlsUseSystemCA\f1 are all mutually
exclusive.
.PP
\fBWindows/macOS Only\f1
.RS
.PP
If using \fB\-\-tlsCertificateSelector\f1\f1 and/or
\fB\-\-tlsClusterCertificateSelector\f1\f1, do \fBnot\f1 use
\fB\-\-tlsCAFile\f1\f1 to specify the root and intermediate CA
certificates. Store all CA certificates required to validate the
full trust chain of the \fB\-\-tlsCertificateSelector\f1\f1 and/or
\fB\-\-tlsClusterCertificateSelector\f1\f1 certificates in the
secure certificate store.
.RE
.PP
For more information about TLS and MongoDB, see
\fBConfigure mongod\f1 and mongos\f1 for TLS/SSL\f1 and
\fBTLS/SSL Configuration for Clients\f1 .
.RE
.PP
\fBmongod \-\-tlsClusterCAFile\f1
.RS
.PP
Specifies the \&.pem file that contains the root certificate
chain from the Certificate Authority used to validate the certificate
presented by a client establishing a connection. Specify the file
name of the \&.pem file using relative or absolute paths.
\fB\-\-tlsClusterCAFile\f1\f1 requires that
\fB\-\-tlsCAFile\f1\f1 is set.
.PP
If \fB\-\-tlsClusterCAFile\f1\f1 does not specify the \&.pem
file for validating the certificate from a client establishing a
connection, the cluster uses the \&.pem file specified in the
\fB\-\-tlsCAFile\f1\f1 option.
.PP
\fB\-\-tlsClusterCAFile\f1\f1 lets you use separate Certificate
Authorities to verify the client to server and server to client
portions of the TLS handshake.
.PP
\fBWindows/macOS Only\f1
.RS
.PP
If using \fB\-\-tlsCertificateSelector\f1\f1 and/or
\fB\-\-tlsClusterCertificateSelector\f1\f1, do \fBnot\f1 use
\fB\-\-tlsClusterCAFile\f1\f1 to specify the root and
intermediate CA certificates. Store all CA certificates required to
validate the full trust chain of the
\fB\-\-tlsCertificateSelector\f1\f1 and/or
\fB\-\-tlsClusterCertificateSelector\f1\f1 certificates in the
secure certificate store.
.RE
.PP
For more information about TLS and MongoDB, see
\fBConfigure mongod\f1 and mongos\f1 for TLS/SSL\f1 and
\fBTLS/SSL Configuration for Clients\f1 .
.RE
.PP
\fBmongod \-\-tlsCRLFile\f1
.RS
.PP
Specifies the \&.pem file that contains the Certificate Revocation
List. Specify the file name of the \&.pem file using relative or
absolute paths.
.RS
.IP \(bu 2
You cannot specify a CRL file on
macOS. Instead, you can use the system SSL certificate store,
which uses OCSP (Online Certificate Status Protocol) to
validate the revocation status of certificates. See
\fB\-\-tlsCertificateSelector\f1\f1 to use the
system SSL certificate store.
.IP \(bu 2
To check for certificate revocation,
MongoDB \fBenables\f1\f1 the use of OCSP
(Online Certificate Status Protocol) by default as an
alternative to specifying a CRL file or using the system SSL
certificate store.
.RE
.PP
For more information about TLS and MongoDB, see
\fBConfigure mongod\f1 and mongos\f1 for TLS/SSL\f1 and
\fBTLS/SSL Configuration for Clients\f1 .
.RE
.PP
\fBmongod \-\-tlsAllowInvalidCertificates\f1
.RS
.PP
Bypasses the validation checks for TLS certificates on other
servers in the cluster and allows the use of invalid certificates to
connect.
.PP
If you specify
\fB\-\-tlsAllowInvalidCertificates\f1 or \fBtls.allowInvalidCertificates:
true\f1 when using x.509 authentication, an invalid certificate is
only sufficient to establish a TLS connection but is
\fIinsufficient\f1 for authentication.
.PP
When using
the \fB\-\-tlsAllowInvalidCertificates\f1\f1 setting, MongoDB
logs a warning regarding the use of the invalid certificate.
.PP
For more information about TLS and MongoDB, see
\fBConfigure mongod\f1 and mongos\f1 for TLS/SSL\f1 and
\fBTLS/SSL Configuration for Clients\f1 .
.RE
.PP
\fBmongod \-\-tlsAllowInvalidHostnames\f1
.RS
.PP
Disables the validation of the hostnames in TLS certificates,
when connecting to other members of the replica set or sharded cluster
for inter\-process authentication. This allows \fBmongod\f1 to connect
to other members if the hostnames in their certificates do not match
their configured hostname.
.PP
For more information about TLS and MongoDB, see
\fBConfigure mongod\f1 and mongos\f1 for TLS/SSL\f1 and
\fBTLS/SSL Configuration for Clients\f1 .
.RE
.PP
\fBmongod \-\-tlsAllowConnectionsWithoutCertificates\f1
.RS
.PP
By default, the server bypasses client certificate validation unless
the server is configured to use a CA file. If a CA file is provided, the
following rules apply:
.RS
.IP \(bu 2
For clients that don\(aqt provide certificates, \fBmongod\f1\f1 or
\fBmongos\f1\f1 encrypts the TLS/SSL connection, assuming the
connection is successfully made.
.IP \(bu 2
For clients that present a certificate, \fBmongod\f1 performs
certificate validation using the root certificate chain specified by
\fB\-\-tlsCAFile\f1\f1  and reject clients with invalid
certificates.
.RE
.PP
Use the \fB\-\-tlsAllowConnectionsWithoutCertificates\f1\f1 option if you have
a mixed deployment that includes clients that do not or cannot present
certificates to the \fBmongod\f1\&.
.PP
For more information about TLS and MongoDB, see
\fBConfigure mongod\f1 and mongos\f1 for TLS/SSL\f1 and
\fBTLS/SSL Configuration for Clients\f1 .
.RE
.PP
\fBmongod \-\-tlsDisabledProtocols\f1
.RS
.PP
Prevents a MongoDB server running with TLS from accepting
incoming connections that use a specific protocol or protocols. To
specify multiple protocols, use a comma separated list of protocols.
.PP
\fB\-\-tlsDisabledProtocols\f1\f1 recognizes the following protocols: \fBTLS1_0\f1, \fBTLS1_1\f1,
\fBTLS1_2\f1, and \fBTLS1_3\f1\&.
.RS
.IP \(bu 2
On macOS, you cannot disable \fBTLS1_1\f1 and leave both \fBTLS1_0\f1 and
\fBTLS1_2\f1 enabled. You must disable at least one of the other
two, for example, \fBTLS1_0,TLS1_1\f1\&.
.IP \(bu 2
To list multiple protocols, specify as a comma separated list of
protocols. For example \fBTLS1_0,TLS1_1\f1\&.
.IP \(bu 2
Specifying an unrecognized protocol prevents the server from
starting.
.IP \(bu 2
The specified disabled protocols overrides any default disabled
protocols.
.RE
.PP
MongoDB disables the use of TLS 1.0 if TLS
1.1+ is available on the system. To enable the disabled TLS 1.0,
specify \fBnone\f1 to \fB\-\-tlsDisabledProtocols\f1\f1\&.
.PP
Members of replica sets and sharded clusters must speak at least one
protocol in common.
.PP
\fBDisallow Protocols\f1
.RE
.PP
\fBmongod \-\-tlsFIPSMode\f1
.RS
.PP
Directs the \fBmongod\f1 to use the FIPS mode of the  TLS
library. Your system must have a FIPS
compliant library to use the \fB\-\-tlsFIPSMode\f1\f1 option.
.PP
FIPS\-compatible TLS/SSL is
available only in MongoDB Enterprise (http://www.mongodb.com/products/mongodb\-enterprise\-advanced?tck=docs_server)\&. See
\fBConfigure MongoDB for FIPS\f1 for more information.
.RE
.SS PROFILER OPTIONS
.PP
\fBmongod \-\-profile\f1
.RS
.PP
\fIDefault\f1: 0
.PP
Configures the \fBdatabase profiler\f1 level.
The following profiler levels are available:
.RS
.IP \(bu 2
.RS
.IP \(bu 4
Level
.IP \(bu 4
Description
.RE
.IP \(bu 2
.RS
.IP \(bu 4
\fB0\f1
.IP \(bu 4
The profiler is off and does not collect any data.
This is the default profiler level.
.RE
.IP \(bu 2
.RS
.IP \(bu 4
\fB1\f1
.IP \(bu 4
The profiler collects data for operations that exceed the
\fBslowms\f1 threshold or match a specified \fBfilter\f1\&.
.IP
When a filter is set:
.RS
.IP \(bu 6
The \fBslowms\f1 and \fBsampleRate\f1 options are not used for
profiling.
.IP \(bu 6
The profiler only captures operations that match the
\fBfilter\f1\&.
.RE
.RE
.IP \(bu 2
.RS
.IP \(bu 4
\fB2\f1
.IP \(bu 4
The profiler collects data for all operations.
.RE
.RE
.PP
Profiling can degrade performance and expose unencrypted query data in the
system log. Carefully consider any performance and security implications
before configuring and enabling the profiler on a production deployment.
.PP
See \fBProfiler Overhead\f1 for more information on
potential performance degradation.
.RE
.PP
\fBmongod \-\-slowms\f1
.RS
.PP
\fIDefault\f1: 100
.PP
The slow operation time threshold, in milliseconds. Operations that run
for longer than this threshold are considered \fIslow\f1\&.
.PP
Slow operations are logged based on \fBworkingMillis\f1, which is the
amount of time that MongoDB spends working on that operation. This means
that factors such as waiting for locks and flow control do not affect
whether an operation exceeds the slow operation threshold.
.PP
When \fBlogLevel\f1\f1 is set to \fB0\f1, MongoDB records \fIslow\f1
operations to the diagnostic log at a rate determined by
\fBslowOpSampleRate\f1\f1\&.
.PP
At higher \fBlogLevel\f1\f1 settings, all operations appear in
the diagnostic log regardless of their latency with the following
exception: the logging of slow oplog entry messages by the
secondaries. The secondaries log only the slow oplog
entries; increasing the \fBlogLevel\f1\f1 does not log all
oplog entries.
.PP
For \fBmongod\f1 instances, \fB\-\-slowms\f1\f1 affects the diagnostic log
and, if enabled, the profiler.
.PP
\fBDatabase Profiler\f1
.RE
.PP
\fBmongod \-\-slowOpSampleRate\f1
.RS
.PP
\fIDefault\f1: 1.0
.PP
The fraction of \fIslow\f1 operations that should be profiled or logged.
\fB\-\-slowOpSampleRate\f1\f1 accepts values between 0 and 1, inclusive.
.PP
\fB\-\-slowOpSampleRate\f1\f1 does not affect the slow oplog entry logging
by the secondary members of a replica set. Secondary
members log all oplog entries that take longer than the slow
operation threshold regardless of the \fB\-\-slowOpSampleRate\f1\f1\&.
.PP
For \fBmongod\f1 instances, \fB\-\-slowOpSampleRate\f1\f1 affects the
diagnostic log and, if enabled, the profiler.
.RE
.SS AUDIT OPTIONS
.PP
\fBmongod \-\-auditCompressionMode\f1
.RS
.PP
Specifies the compression mode for \fBaudit log encryption\f1\&. You must also enable audit log
encryption using either \fB\-\-auditEncryptionKeyUID\f1\f1 or
\fB\-\-auditLocalKeyFile\f1\f1\&.
.PP
\fB\-\-auditCompressionMode\f1\f1 can be set to one of these values:
.RS
.IP \(bu 2
.RS
.IP \(bu 4
Value
.IP \(bu 4
Description
.RE
.IP \(bu 2
.RS
.IP \(bu 4
\fBzstd\f1
.IP \(bu 4
Use the \fBzstd\f1 algorithm to compress the audit log.
.RE
.IP \(bu 2
.RS
.IP \(bu 4
\fBnone\f1 \fI(default)\f1
.IP \(bu 4
Do not compress the audit log.
.RE
.RE
.PP
Available only in MongoDB Enterprise (http://www.mongodb.com/products/mongodb\-enterprise\-advanced?tck=docs_server)\&.
MongoDB Enterprise and Atlas have different configuration
requirements.
.RE
.PP
\fBmongod \-\-auditDestination\f1
.RS
.PP
Enables \fBauditing\f1 and specifies where
\fBmongod\f1 sends all audit events.
.PP
\fB\-\-auditDestination\f1\f1 can have one of the following values:
.RS
.IP \(bu 2
.RS
.IP \(bu 4
Value
.IP \(bu 4
Description
.RE
.IP \(bu 2
.RS
.IP \(bu 4
\fBsyslog\f1
.IP \(bu 4
Output the audit events to syslog in JSON format. Not available on
Windows. Audit messages have a syslog severity level of \fBinfo\f1
and a facility level of \fBuser\f1\&.
.IP
The syslog message limit can result in the truncation of
audit messages. The auditing system neither detects the
truncation nor errors upon its occurrence.
.RE
.IP \(bu 2
.RS
.IP \(bu 4
\fBconsole\f1
.IP \(bu 4
Output the audit events to \fBstdout\f1 in JSON format.
.RE
.IP \(bu 2
.RS
.IP \(bu 4
\fBfile\f1
.IP \(bu 4
Output the audit events to the file specified in
\fB\-\-auditPath\f1\f1 in the format specified in
\fB\-\-auditFormat\f1\f1\&.
.RE
.RE
.PP
Available only in MongoDB Enterprise (http://www.mongodb.com/products/mongodb\-enterprise\-advanced?tck=docs_server)
and MongoDB Atlas (https://cloud.mongodb.com/user#/atlas/login)\&.
.RE
.PP
\fBmongod \-\-auditEncryptionKeyUID\f1
.RS
.PP
Specifies the unique identifier of the Key Management
Interoperability Protocol (KMIP) key for \fBaudit log encryption\f1\&.
.PP
You cannot use \fB\-\-auditEncryptionKeyUID\f1\f1 and
\fB\-\-auditLocalKeyFile\f1\f1 together.
.PP
Available only in MongoDB Enterprise (http://www.mongodb.com/products/mongodb\-enterprise\-advanced?tck=docs_server)\&.
MongoDB Enterprise and Atlas have different configuration
requirements.
.RE
.PP
\fBmongod \-\-auditFormat\f1
.RS
.PP
Specifies the format of the output file for \fBauditing\f1 if \fB\-\-auditDestination\f1\f1 is \fBfile\f1\&. The
\fB\-\-auditFormat\f1\f1 option can have one of the following values:
.RS
.IP \(bu 2
.RS
.IP \(bu 4
Value
.IP \(bu 4
Description
.RE
.IP \(bu 2
.RS
.IP \(bu 4
\fBJSON\f1
.IP \(bu 4
Output the audit events in JSON format to the file specified
in \fB\-\-auditPath\f1\f1\&.
.RE
.IP \(bu 2
.RS
.IP \(bu 4
\fBBSON\f1
.IP \(bu 4
Output the audit events in BSON binary format to the file
specified in \fB\-\-auditPath\f1\f1\&.
.RE
.RE
.PP
Printing audit events to a file in JSON format degrades server
performance more than printing to a file in BSON format.
.PP
Available only in MongoDB Enterprise (http://www.mongodb.com/products/mongodb\-enterprise\-advanced?tck=docs_server)
and MongoDB Atlas (https://cloud.mongodb.com/user#/atlas/login)\&.
.RE
.PP
\fBmongod \-\-auditLocalKeyFile\f1
.RS
.PP
Specifies the path and file name for a local audit key file for
\fBaudit log encryption\f1\&.
.PP
Only use \fB\-\-auditLocalKeyFile\f1\f1 for testing because the key is
not secured. To secure the key, use
\fB\-\-auditEncryptionKeyUID\f1\f1 and an external Key
Management Interoperability Protocol (KMIP) server.
.PP
You cannot use \fB\-\-auditLocalKeyFile\f1\f1 and
\fB\-\-auditEncryptionKeyUID\f1\f1 together.
.PP
Available only in MongoDB Enterprise (http://www.mongodb.com/products/mongodb\-enterprise\-advanced?tck=docs_server)\&.
MongoDB Enterprise and Atlas have different configuration
requirements.
.RE
.PP
\fBmongod \-\-auditPath\f1
.RS
.PP
Specifies the output file for auditing if
\fB\-\-auditDestination\f1\f1 has value of \fBfile\f1\&. The
\fB\-\-auditPath\f1\f1 option can take either a full path name or a
relative path name.
.PP
Available only in MongoDB Enterprise (http://www.mongodb.com/products/mongodb\-enterprise\-advanced?tck=docs_server)
and MongoDB Atlas (https://cloud.mongodb.com/user#/atlas/login)\&.
.RE
.PP
\fBmongod \-\-auditFilter\f1
.RS
.PP
Specifies the filter to limit the \fBtypes of operations\f1 the \fBaudit system\f1 records. The option takes a string representation
of a query document of the form:
.PP
.EX
  { <field1>: <expression1>, ... }
.EE
.PP
The \fB<field>\f1 can be \fBany field in the audit message\f1, including fields returned in the
\fBparam\f1 document. The
\fB<expression>\f1 is a \fBquery condition expression\f1\&.
.PP
To specify an audit filter, enclose the filter document in single
quotes to pass the document as a string.
.PP
To specify the audit filter in a \fBconfiguration file\f1, you must use the YAML format of
the configuration file.
.PP
Available only in MongoDB Enterprise (http://www.mongodb.com/products/mongodb\-enterprise\-advanced?tck=docs_server)
and MongoDB Atlas (https://cloud.mongodb.com/user#/atlas/login)\&.
.RE
.PP
\fBmongod \-\-auditSchema\f1
.RS
.PP
\fIDefault\f1: \fBmongo\f1
.PP
Specifies the format used for audit logs. You can specify one of the
following values for \fB\-\-auditSchema\f1:
.RS
.IP \(bu 2
.RS
.IP \(bu 4
Value
.IP \(bu 4
Description
.RE
.IP \(bu 2
.RS
.IP \(bu 4
\fBmongo\f1
.IP \(bu 4
Logs are written in a format designed by MongoDB.
.IP
For example log messages, see \fBmongo Schema Audit Messages\f1\&.
.RE
.IP \(bu 2
.RS
.IP \(bu 4
\fBOCSF\f1
.IP \(bu 4
Logs are written in OCSF (Open Cybersecurity Schema
Framework) format. This option provides logs in a standardized
format compatible with log processors.
.IP
For example log messages, see \fBOCSF Schema Audit Messages\f1\&.
.RE
.RE
.RE
.SS INMEMORY OPTIONS
.PP
\fBmongod \-\-inMemorySizeGB\f1
.RS
.PP
\fIDefault\f1: 50% of physical RAM minus 1 GB.
.PP
Maximum amount of memory to allocate for the \fBin\-memory storage
engine\f1 data, including indexes, the oplog (if the
\fBmongod\f1 is part of a replica set), sharded
cluster metadata, etc.
.PP
Values can range from 256MB to 10TB and can be a float.
.PP
By default, the in\-memory storage engine uses 50% of physical RAM minus
1 GB.
.PP
Available in MongoDB Enterprise only.
.RE
.SS ENCRYPTION KEY MANAGEMENT OPTIONS
.PP
\fBmongod \-\-enableEncryption\f1
.RS
.PP
\fIDefault\f1: false
.PP
Enables encryption for the WiredTiger storage engine. This option
must be enabled in order to pass in encryption keys and
configurations.
.PP
Available in MongoDB Enterprise only.
.RE
.PP
\fBmongod \-\-encryptionCipherMode\f1
.RS
.PP
\fIDefault\f1: AES256\-CBC
.PP
The cipher mode to use for encryption at rest:
.RS
.IP \(bu 2
.RS
.IP \(bu 4
Mode
.IP \(bu 4
Description
.RE
.IP \(bu 2
.RS
.IP \(bu 4
\fBAES256\-CBC\f1
.IP \(bu 4
256\-bit Advanced Encryption Standard in Cipher Block Chaining Mode
.RE
.IP \(bu 2
.RS
.IP \(bu 4
\fBAES256\-GCM\f1
.IP \(bu 4
256\-bit Advanced Encryption Standard in Galois/Counter Mode
.IP
Available only on Linux.
.IP
MongoDB Enterprise on Windows no longer supports \fBAES256\-GCM\f1 as a
block cipher for encryption at rest. This usage is only supported on Linux.
.RE
.RE
.PP
Available in MongoDB Enterprise only.
.RE
.PP
\fBmongod \-\-encryptionKeyFile\f1
.RS
.PP
The path to the local keyfile when managing keys via process \fIother
than\f1 KMIP. Only set when managing keys via process other than KMIP.
If data is already encrypted using KMIP, MongoDB throws an error.
.PP
The keyfile can contain only a single key. The key is either a 16 or
32 character string.
.PP
Requires \fB\-\-enableEncryption\f1\f1\&.
.PP
Available in MongoDB Enterprise only.
.RE
.PP
\fBmongod \-\-kmipKeyIdentifier\f1
.RS
.PP
Unique KMIP identifier for an existing key within the KMIP server.
Include to use the key associated with the identifier as the system
key. You can only use the setting the first time you enable
encryption for the \fBmongod\f1 instance. Requires
\fB\-\-enableEncryption\f1\f1\&.
.PP
If unspecified, MongoDB requests that the KMIP server create a
new key to utilize as the system key.
.PP
If the KMIP server cannot locate a key with the specified identifier
or the data is already encrypted with a key, MongoDB throws an
error
.PP
Available in MongoDB Enterprise only.
.RE
.PP
\fBmongod \-\-kmipRotateMasterKey\f1
.RS
.PP
\fIDefault\f1: false
.PP
If true, rotate the master key and re\-encrypt the internal
keystore.
.PP
Available in MongoDB Enterprise only.
.PP
\fBKMIP Master Key Rotation\f1
.RE
.PP
\fBmongod \-\-kmipServerName\f1
.RS
.PP
Hostname or IP address of the KMIP server to connect to. Requires
\fB\-\-enableEncryption\f1\f1\&.
.PP
You can specify multiple KMIP servers as a comma\-separated list, for example:
\fBserver1.example.com,server2.example.com\f1\&. On startup, the
\fBmongod\f1 attempts to establish a connection to each
server in the order listed, and selects the first server to
which it can successfully establish a connection. KMIP server
selection occurs only at startup.
.PP
When connecting to a KMIP server, the \fBmongod\f1
verifies that the specified \fB\-\-kmipServerName\f1\f1 matches the
Subject Alternative Name \fBSAN\f1 (or, if \fBSAN\f1 is not present, the
Common Name \fBCN\f1) in the certificate presented by the KMIP server.
If \fBSAN\f1 is present, \fBmongod\f1 does not match against
the \fBCN\f1\&. If the hostname does not match the \fBSAN\f1 (or \fBCN\f1),
the \fBmongod\f1 fails to connect.
.PP
Starting in MongoDB 4.2, when performing comparison of SAN, MongoDB
supports comparison of DNS names or IP addresses. In previous versions,
MongoDB only supports comparisons of DNS names.
.PP
Available in MongoDB Enterprise only.
.RE
.PP
\fBmongod \-\-kmipPort\f1
.RS
.PP
\fIDefault\f1: 5696
.PP
Port number to use to communicate with the KMIP server.
Requires \fB\-\-kmipServerName\f1\f1\&. Requires
\fB\-\-enableEncryption\f1\f1\&.
.PP
If specifying multiple KMIP servers with \fB\-\-kmipServerName\f1\f1,
the \fBmongod\f1 uses the port specified with
\fB\-\-kmipPort\f1\f1 for all provided KMIP servers.
.PP
Available in MongoDB Enterprise only.
.RE
.PP
\fBmongod \-\-kmipConnectRetries\f1
.RS
.PP
\fIDefault\f1: 0
.PP
How many times to retry the initial connection to the KMIP server.
Use together with \fB\-\-kmipConnectTimeoutMS\f1\f1 to
control how long the \fBmongod\f1 waits for a response
between each retry.
.PP
Available in MongoDB Enterprise only.
.RE
.PP
\fBmongod \-\-kmipConnectTimeoutMS\f1
.RS
.PP
\fIDefault\f1: 5000
.PP
Timeout in milliseconds to wait for a response from the KMIP server.
If the \fB\-\-kmipConnectRetries\f1\f1 setting is specified,
the \fBmongod\f1 waits for the specified interval between retries.
.PP
Value must be \fB1000\f1 or greater.
.PP
Available in MongoDB Enterprise only.
.RE
.PP
\fBmongod \-\-kmipClientCertificateSelector\f1
.RS
.PP
Available on Windows and macOS as an alternative to
\fB\-\-kmipClientCertificateFile\f1\f1\&.
.PP
\fB\-\-kmipClientCertificateFile\f1\f1 and \fB\-\-kmipClientCertificateSelector\f1\f1 options are mutually exclusive. You can only
specify one.
.PP
Specifies a certificate property in order to select a matching
certificate from the operating system\(aqs certificate store to
authenticate MongoDB to the KMIP server.
.PP
\fB\-\-kmipClientCertificateSelector\f1\f1 accepts an argument of the format \fB<property>=<value>\f1
where the property can be one of the following:
.RS
.IP \(bu 2
.RS
.IP \(bu 4
Property
.IP \(bu 4
Value type
.IP \(bu 4
Description
.RE
.IP \(bu 2
.RS
.IP \(bu 4
\fBsubject\f1
.IP \(bu 4
ASCII string
.IP \(bu 4
Subject name or common name on certificate
.RE
.IP \(bu 2
.RS
.IP \(bu 4
\fBthumbprint\f1
.IP \(bu 4
hex string
.IP \(bu 4
A sequence of bytes, expressed as hexadecimal, used to
identify a public key by its SHA\-1 digest.
.IP
The \fBthumbprint\f1 is sometimes referred to as a
\fBfingerprint\f1\&.
.RE
.RE
.PP
Available in MongoDB Enterprise only.
.RE
.PP
\fBmongod \-\-kmipClientCertificateFile\f1
.RS
.PP
Path to the \fB\&.pem\f1 file used to authenticate MongoDB to the KMIP
server. The specified \fB\&.pem\f1 file must contain both the TLS/SSL
certificate and key.
.PP
To use this option, you must also specify the
\fB\-\-kmipServerName\f1\f1 option.
.PP
Enabling encryption using a KMIP server on Windows fails when using
\fB\-\-kmipClientCertificateFile\f1 and the KMIP server enforces TLS 1.2.
.PP
To enable encryption at rest with KMIP on Windows, you must:
.RS
.IP \(bu 2
Import the client certificate into the Windows Certificate Store.
.IP \(bu 2
Use the \fB\-\-kmipClientCertificateSelector\f1\f1 option.
.RE
.PP
On macOS or Windows, you can use a certificate
from the operating system\(aqs secure store instead of a PEM key
file. See \fB\-\-kmipClientCertificateSelector\f1\f1\&.
.PP
Available in MongoDB Enterprise only.
.RE
.PP
\fBmongod \-\-kmipClientCertificatePassword\f1
.RS
.PP
The password (if one exists) for the client certificate passed into
\fB\-\-kmipClientCertificateFile\f1\f1\&. Is used for
authenticating MongoDB to the KMIP server. Requires that a
\fB\-\-kmipClientCertificateFile\f1\f1 be provided.
.PP
Available in MongoDB Enterprise only.
.RE
.PP
\fBmongod \-\-kmipServerCAFile\f1
.RS
.PP
Path to CA File. Used for validating secure client connection to
KMIP server.
.PP
On macOS or Windows, you can use a certificate
from the operating system\(aqs secure store instead of a PEM key
file. See \fB\-\-kmipClientCertificateSelector\f1\f1\&. When using the secure
store, you do not need to, but can, also specify the \fB\-\-kmipServerCAFile\f1\f1\&.
.RE
.PP
\fBmongod \-\-kmipActivateKeys\f1
.RS
.PP
\fIDefault\f1: true
.PP
Activates all newly created KMIP keys upon creation and then periodically
checks those keys are in an active state.
.PP
When \fB\-\-kmipActivateKeys\f1 is \fBtrue\f1 and you have existing keys on a
KMIP server, the key must be activated first or the \fBmongod\f1\f1
node fails to start.
.PP
If the key being used by the mongod transitions into a non\-active state,
the \fBmongod\f1\f1 node shuts down unless \fBkmipActivateKeys\f1 is
false. To ensure you have an active key, rotate the KMIP master key by
using \fB\-\-kmipRotateMasterKey\f1\f1\&.
.RE
.PP
\fBmongod \-\-kmipKeyStatePollingSeconds\f1
.RS
.PP
\fIDefault\f1: 900 seconds
.PP
Frequency in seconds at which \fBmongod\f1 polls the KMIP server for
active keys.
.PP
To disable disable polling, set the value to \fB\-1\f1\&.
.RE
.PP
\fBmongod \-\-kmipUseLegacyProtocol\f1
.RS
.PP
\fIDefault\f1: false
.PP
When \fBtrue\f1, \fBmongod\f1 uses KMIP protocol version 1.0 or 1.1 instead
of the default version. The default KMIP protocol is version 1.2.
.PP
To use \fBaudit log encryption\f1
with KMIP version 1.0 or 1.1, you must specify
\fBauditEncryptKeyWithKMIPGet\f1\f1 at startup.
.RE
.PP
\fBmongod \-\-eseDatabaseKeyRollover\f1
.RS
.PP
Roll over the \fBencrypted storage engine\f1 database keys configured with
\fBAES256\-GCM\f1 cipher.
.PP
When \fBmongod\f1 instance is started with this option, the
instance rotates the keys and exits.
.PP
Available in MongoDB Enterprise only.
.RE