If I try to run mongod 3.1.7 with sharding.configsvrMode specified in the yaml configuration file, mongod complains "Unrecognized option: sharding.configsvrMode". This does not happen if I instead specify --configsvrMode on the command line.
[tim@neurofunk dbs]$ cat cfg1/mongod.conf net: port: 9007 replication: replSetName: csrs sharding: clusterRole: configsvr configsvrMode: sccc storage: dbPath: /Users/tim/dbs/cfg1 [tim@neurofunk dbs]$ /tmp/mms-automation/test/versions/mongodb-osx-x86_64-3.1.7/bin/mongod -f cfg1/mongod.conf Unrecognized option: sharding.configsvrMode try '/tmp/mms-automation/test/versions/mongodb-osx-x86_64-3.1.7/bin/mongod --help' for more information [tim@neurofunk dbs]$