MongoDB Documentation, Release 3.0.4 To fix the settings before upgrading to MongoDB 3.0, connect to the primary and reconfigure your replica set to valid configuration settings. If you have already upgraded to MongoDB 3.0, you must downgrade to MongoDB 2.6 (page 821) first and then fix the settings. Once you have reconfigured the replica set, you can re-upgrade to MongoDB 3.0. Change of w: majority Semantics A write concern with a w: majority (page 130) value is satisfied when a majority of the voting members replicates a write operation. In previous versions, majority referred a majority of all voting and non-voting members of the set. Remove local.slaves Collection MongoDB 3.0 removes the local.slaves collection that tracked the sec- ondaries’ replication progress. To track the replication progress, use the rs.status() method. Replica Set State Change The FATAL replica set state does not exist as of 3.0.0. HTTP Interface The HTTP Interface (i.e. net.http.enabled ) no longer reports replication data. MongoDB Tools Changes Require a Running MongoDB Instance The 3.0 versions of MongoDB tools, mongodump , mongorestore , mongoexport , mongoimport , mongofiles , and mongooplog , must connect to running MongoDB instances and these tools cannot directly modify the data files with --dbpath as in previous versions. Ensure that you start your mongod instance(s) before using these tools. MongoDB Tools Enhancements (page 802) Remove releaseConnectionsAfterResponse Parameter MongoDB now always releases connections af- ter response. releaseConnectionsAfterResponse parameter is no longer available. Security Changes Sharded Cluster Setting See also: Removed Options • Removed --dbpath , --journal , and --filter options for mongodump , mongorestore , mongoimport , mongoexport , and bsondump . • Removed --locks option for mongotop . • Removed --noobjcheck option for bsondump and mongorestore . • Removed --csv option for mongoexport . Use the new --type option to specify the export format type ( csv or json ). 806 Chapter 12. Release Notes