- Storage >
- Storage Engines >
- WiredTiger Storage Engine >
- Change Sharded Cluster to WiredTiger
Change Sharded Cluster to WiredTiger¶
Starting in version 3.2, WiredTiger is the default storage engine for MongoDB.
Use this tutorial to update MongoDB 3.4 sharded clusters to use WiredTiger.
For earlier versions of MongoDB:
- To convert a 3.2 sharded cluster that uses MMAPv1, see the MongoDB 3.2 manual.
- To convert a 3.0 sharded cluster that uses MMAPv1, see the MongoDB 3.0 manual.
Considerations¶
Downtime¶
This procedure may involve downtime, especially if one or more of your shards is a standalone. If you change the host or port of any shard, you must update the shard configuration as well.
MongoDB 3.0 or Greater¶
Config Servers¶
Starting in version 3.4, config servers must be deployed as replica sets (CSRS). As such, version 3.4+ config servers already use the WiredTiger storage engine.
XFS and WiredTiger¶
With the WiredTiger storage engine, using XFS for data bearing nodes is recommended on Linux. For more information, see Kernel and File Systems.
Change Shards to WiredTiger¶
Note
A sharded cluster can have mixed storage engines for its individual shards.
To change the storage engine for the shards to WiredTiger, refer to the appropriate procedure for each shard:
- If the shard is a standalone, see Change Standalone to WiredTiger.
- If the shard is a replica set, see Change Replica Set to WiredTiger.