- Reference >
mongoShell Methods >- Replication Methods >
- rs.initiate()
rs.initiate()¶
On this page
Description¶
-
rs.initiate(configuration)¶ Initiates a replica set. Optionally, the method can take an argument in the form of a document that holds the configuration of a replica set.
The
rs.initiate()method has the following parameter:Parameter Type Description configurationdocument Optional. A document that specifies configuration for the new replica set. If a configuration is not specified, MongoDB uses a default replica set configuration. The
rs.initiate()method provides a wrapper around thereplSetInitiatecommand.
Replica Set Configuration¶
See Replica Set Configuration Document Example for details of replica set configuration document.
Example¶
The following operation initiates a new replica set with three members.
The three mongod instances must have started with the
--replSet command line option, or
replication.replSetName if using a configuration file, set
to myReplSet:
Connect to one of the mongod instances and run
rs.initiate().
Note
Run the method on only one of the mongod instances.
rs.initiate(
{
_id: "myReplSet",
version: 1,
members: [
{ _id: 0, host : "mongodb0.example.net:27017" },
{ _id: 1, host : "mongodb1.example.net:27017" },
{ _id: 2, host : "mongodb2.example.net:27017" }
]
}
)
For details on replica set configuration, see Replica Set Configuration Fields.
For details on deploying a replica set, see Deploy a Replica Set.
See also