allow reconfig on secondary on startup

db/repl.h

@@ -59,6 +59,7 @@ namespace mongo {
         int slavedelay;
 
         set<string> discoveredSeeds;
+        BSONObj reconfig;
 
         ReplSettings()
             : slave(NotSlave) , master(false) , fastsync() , autoresync(false), slavedelay(), discoveredSeeds() {

db/repl/replset_commands.cpp

@@ -17,6 +17,7 @@
 #include "pch.h"
 #include "../cmdline.h"
 #include "../commands.h"
+#include "../repl.h"
 #include "health.h"
 #include "rs.h"
 #include "rs_config.h"
@@ -138,10 +139,22 @@ namespace mongo {
         }
     private:
         bool _run(const string& , BSONObj& cmdObj, string& errmsg, BSONObjBuilder& result, bool fromRepl) {
-            if( !check(errmsg, result) )
+            if( cmdObj["replSetReconfig"].type() != Object ) {
+                errmsg = "no configuration specified";
                 return false;
+            }
 
             bool force = cmdObj.hasField("force") && cmdObj["force"].trueValue();
+            if( force && !theReplSet ) {
+                replSettings.reconfig = cmdObj["replSetReconfig"].Obj().getOwned();
+                result.append("msg", "will try this config momentarily, try running rs.conf() again in a few seconds");
+                return true;
+            }
+
+            if ( !check(errmsg, result) ) {
+                return false;
+            }
+
             if( !force && !theReplSet->box.getState().primary() ) {
                 errmsg = "replSetReconfig command must be sent to the current replica set primary.";
                 return false;
@@ -159,11 +172,6 @@ namespace mongo {
                 }
             }
 
-            if( cmdObj["replSetReconfig"].type() != Object ) {
-                errmsg = "no configuration specified";
-                return false;
-            }
-
             try {
                 ReplSetConfig newConfig(cmdObj["replSetReconfig"].Obj(), force);
 

db/repl/rs.cpp

@@ -566,6 +566,16 @@ namespace mongo {
                     }
                 }
 
+                if (!replSettings.reconfig.isEmpty()) {
+                    try {
+                        configs.push_back(ReplSetConfig(replSettings.reconfig, true));
+                    }
+                    catch( DBException& re) {
+                        log() << "couldn't load reconfig: " << re.what() << endl;
+                        replSettings.reconfig = BSONObj();
+                    }
+                }
+
                 int nok = 0;
                 int nempty = 0;
                 for( vector<ReplSetConfig>::iterator i = configs.begin(); i != configs.end(); i++ ) {

jstests/replsets/fastsync.js

@@ -22,7 +22,7 @@ var wait = function(f) {
 }
 
 var reconnect = function(a) {
-  wait(function() { 
+  wait(function() {
       try {
         a.getDB("foo").bar.stats();
         return true;
@@ -59,7 +59,7 @@ while (count < 10 && result.ok != 1) {
   count++;
   sleep(2000);
   result = admin.runCommand({replSetInitiate : config});
-}   
+}
 
 assert(result.ok, tojson(result));
 assert.soon(function() { result = false;
@@ -110,11 +110,11 @@ while (status.members[1].state != 2 && count < 200) {
     printjson(status);
   }
   assert(!status.members[1].errmsg || !status.members[1].errmsg.match("^initial sync cloning db"));
-  
+
   sleep(1000);
 
   // disconnection could happen here
-  try {  
+  try {
     status = admin.runCommand({replSetGetStatus : 1});
   }
   catch (e) {
@@ -124,3 +124,36 @@ while (status.members[1].state != 2 && count < 200) {
 }
 
 assert.eq(status.members[1].state, 2);
+
+print("restart member with a different port and make it a new set");
+try {
+  p.getDB("admin").runCommand({shutdown:1});
+}
+catch(e) {
+  print("good, shutting down: " +e);
+}
+sleep(10000);
+
+pargs = new MongodRunner( ports[ 2 ], basePath + "-p", false, false,
+                          ["--replSet", basename, "--oplogSize", 2],
+                          {no_bind : true} );
+p = pargs.start(true);
+
+printjson(p.getDB("admin").runCommand({replSetGetStatus:1}));
+
+p.getDB("admin").runCommand({replSetReconfig : {
+      _id : basename,
+      members : [{_id:0, host : hostname+":"+ports[2]}]
+        }, force : true});
+
+print("start waiting for primary...");
+assert.soon(function() {
+    try {
+      return p.getDB("admin").runCommand({isMaster : 1}).ismaster;
+    }
+    catch(e) {
+      print(e);
+    }
+    return false;
+  }, "waiting for master", 60000);
+