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- rs.add()
rs.add()¶
-
rs.
add
(hostspec, arbiterOnly)¶ Specify one of the following forms:
Parameters: - host (string,document) – Either a string or a document. If a string, specifies a host (and optionally port-number) for a new host member for the replica set; MongoDB will add this host with the default configuration. If a document, specifies any attributes about a member of a replica set.
- arbiterOnly (boolean) – Optional. If
true
, this host is an arbiter. If the second argument evaluates totrue
, as is the case with some documents, then this instance will become an arbiter.
Provides a simple method to add a member to an existing replica set. You can specify new hosts in one of two ways:
- as a “hostname” with an optional port number to use the default configuration as in the Add a Member to an Existing Replica Set example.
- as a configuration document, as in the Add a Member to an Existing Replica Set (Alternate Procedure) example.
This function will disconnect the shell briefly and forces a reconnection as the replica set renegotiates which node will be primary. As a result, the shell will display an error even if this command succeeds.
rs.add()
provides a wrapper around some of the functionality of the “replSetReconfig
” database command and the corresponding shell helperrs.reconfig()
. See the Replica Set Configuration document for full documentation of all replica set configuration options.Example
To add a
mongod
accessible on the default port27017
running on the hostmongodb3.example.net
, use the followingrs.add()
invocation:If
mongodb3.example.net
is an arbiter, use the following form:To add
mongodb3.example.net
as a secondary-only member of set, use the following form ofrs.add()
:Replace,
3
with the next unused_id
value in the replica set. Seers.conf()
to see the existing_id
values in the replica set configuration document.See the Replica Set Configuration and Replica Set Operation and Management documents for more information.