sh.addShard()
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Definition
sh.addShard(<url>)
Adds a shard replica set to a sharded cluster. This method must be run on a
mongos
instance.Important
mongosh Method
This page documents a
mongosh
method. This is not the documentation for database commands or language-specific drivers, such as Node.js.For the database command, see the
addShard
command.For MongoDB API drivers, refer to the language-specific MongoDB driver documentation.
The
sh.addShard()
method has the following parameter:ParameterTypeDescriptionhost
stringThe replica set name, hostname, and port of at least one member of the shard's replica set. Any additional replica set member hostnames must be comma separated. For example:
<replica_set>/<hostname><:port>,<hostname><:port>, ... The
sh.addShard()
method has the following prototype form:sh.addShard("<replica_set>/<hostname><:port>") Warning
mongos
uses"majority"
for theaddShard
command and its helpersh.addShard()
.
Compatibility
This method is available in deployments hosted in the following environments:
MongoDB Atlas: The fully managed service for MongoDB deployments in the cloud
Important
This command is not supported in M0, M2, and M5 clusters. For more information, see Unsupported Commands.
MongoDB Enterprise: The subscription-based, self-managed version of MongoDB
MongoDB Community: The source-available, free-to-use, and self-managed version of MongoDB
Considerations
Balancing
When you add a shard to a sharded cluster, you affect the balance of chunks among the shards of a cluster for all existing sharded collections. The balancer will begin migrating chunks so that the cluster will achieve balance. See Balancer Internals for more information.
Hidden Members
Important
You cannot include a hidden member in the seed list provided to
sh.addShard()
.
Example
To add a shard, specify the name of the replica set and the hostname of at least one member of the replica set, as a seed. If you specify additional hostnames, all must be members of the same replica set.
The following example adds a replica set named repl0
and specifies
one member of the replica set:
sh.addShard("repl0/mongodb3.example.net:27327")