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- replSetGetConfig
replSetGetConfig¶
New in version 3.0.0.
On this page
Definition¶
-
replSetGetConfig
¶ Returns a document that describes the current configuration of the replica set. To invoke the command directly, use the following operation:
In the
mongo
shell, you can access the data provided byreplSetGetConfig
using thers.conf()
method, as in the following:
Output Example¶
The following document provides a representation of a replica set configuration document. The configuration of your replica set may include only a subset of these settings:
Replica Set Configuration Fields¶
-
replSetGetConfig.
_id
¶ Type: string
The name of the replica set. Once set, you cannot change the name of a replica set.
_id
must be identical to thereplication.replSetName
or the value of –replSet specified tomongod
on the command line.See
replSetName
or--replSet
for information on setting the replica set name.
-
replSetGetConfig.
version
¶ An incrementing number used to distinguish revisions of the replica set configuration object from previous iterations of the configuration.
members
¶
-
replSetGetConfig.
members
¶ Type: array
An array of member configuration documents, one for each member of the replica set. The
members
array is a zero-indexed array.Each member-specific configuration document can contain the following fields:
-
replSetGetConfig.members[n].
_id
¶ Type: integer
A numeric identifier of every member in the replica set. Once set, you cannot change the
_id
of a member.
-
replSetGetConfig.members[n].
host
¶ Type: string
The hostname and, if specified, the port number, of the set member.
The hostname name must be resolvable for every host in the replica set.
Warning
host
cannot hold a value that resolves tolocalhost
or the local interface unless all members of the set are on hosts that resolve tolocalhost
.
-
replSetGetConfig.members[n].
arbiterOnly
¶ Optional.
Type: boolean
Default: false
A boolean that identifies an arbiter. A value of
true
indicates that the member is an arbiter.When using the
rs.addArb()
method to add an arbiter, the method automatically setsarbiterOnly
totrue
for the added member.
-
replSetGetConfig.members[n].
buildIndexes
¶ Optional.
Type: boolean
Default: true
A boolean that indicates whether the
mongod
builds indexes on this member. You can only set this value when adding a member to a replica set. You cannot changebuildIndexes
field after the member has been added to the set. To add a member, seers.add()
andrs.reconfig()
.Do not set to
false
formongod
instances that receive queries from clients.Setting
buildIndexes
tofalse
may be useful if all the following conditions are true:- you are only using this instance to perform backups using
mongodump
, and - this member will receive no queries, and
- index creation and maintenance overburdens the host system.
Even if set to
false
, secondaries will build indexes on the_id
field in order to facilitate operations required for replication.Warning
If you set
buildIndexes
tofalse
, you must also setpriority
to0
. Ifpriority
is not0
, MongoDB will return an error when attempting to add a member withbuildIndexes
equal tofalse
.To ensure the member receives no queries, you should make all instances that do not build indexes hidden.
Other secondaries cannot replicate from a member where
buildIndexes
is false.- you are only using this instance to perform backups using
Optional.
Type: boolean
Default: false
When this value is
true
, the replica set hides this instance and does not include the member in the output ofdb.isMaster()
orisMaster
. This prevents read operations (i.e. queries) from ever reaching this host by way of secondary read preference.See also
-
replSetGetConfig.members[n].
priority
¶ Optional.
Type: Number, between 0 and 1000.
Default: 1.0
A number that indicates the relative eligibility of a member to become a primary.
Specify higher values to make a member more eligible to become primary, and lower values to make the member less eligible. Priorities are only used in comparison to each other. Members of the set will veto election requests from members when another eligible member has a higher priority value. Changing the balance of priority in a replica set will trigger an election.
A
priority
of0
makes it impossible for a member to become primary.See also
Optional.
Type: document
Default: none
A tag set document containing mappings of arbitrary keys and values. These documents describe replica set members in order to customize write concern and read preference and thereby allow configurable data center awareness.
This field is only present if there are tags assigned to the member. See Configure Replica Set Tag Sets for more information.
Use
tags
to configure write concerns in conjunction withgetLastErrorModes
andgetLastErrorDefaults
.Important
In tag sets, all tag values must be strings.
For more information on configuring tag sets for read preference and write concern, see Configure Replica Set Tag Sets.
-
replSetGetConfig.members[n].
slaveDelay
¶ Optional.
Type: integer
Default: 0
The number of seconds “behind” the primary that this replica set member should “lag”.
Use this option to create delayed members. Delayed members maintain a copy of the data that reflects the state of the data at some time in the past.
See also
-
replSetGetConfig.members[n].
votes
¶ Optional.
Type: integer
Default: 1
The number of votes a server will cast in a replica set election. The number of votes each member has is either
1
or0
, and arbiters always have exactly1
vote.A replica set can have up to
50 members
but only 7 voting members. If you need more than 7 members in one replica set, setvotes
to0
for the additional non-voting members.Changed in version 3.0.0: Members cannot have
votes
greater than1
. For details, see Replica Set Configuration Validation.
-
settings
¶
-
replSetGetConfig.
settings
¶ Optional.
Type: document
A document that contains configuration options that apply to the whole replica set.
The
settings
document contain the following fields:-
replSetGetConfig.settings.
chainingAllowed
¶ Optional.
Type: boolean
Default: true
When
chainingAllowed
istrue
, the replica set allows secondary members to replicate from other secondary members. WhenchainingAllowed
isfalse
, secondaries can replicate only from the primary.See also
-
replSetGetConfig.settings.
getLastErrorDefaults
¶ Optional.
Type: document
A document that specifies the write concern for the replica set. The replica set will use this write concern only when write operations or
getLastError
specify no other write concern.If
getLastErrorDefaults
is not set, the default write concern for the replica set only requires confirmation from the primary.
-
replSetGetConfig.settings.
getLastErrorModes
¶ Optional.
Type: document
A document used to define an extended write concern through the use of
tags
. The extended write concern can provide data-center awareness.For example, the following document defines an extended write concern named
eastCoast
and associates with a write to a member that has theeast
tag.Write operations to the replica set can use the extended write concern, e.g.
{ w: "eastCoast" }
.See Configure Replica Set Tag Sets for more information and example.
-
replSetGetConfig.settings.
heartbeatTimeoutSecs
¶ Optional.
Type: int
Default: 10
Number of seconds that the replica set members wait for a successful heartbeat from each other. If a member does not respond in time, other members mark the delinquent member as inaccessible.
-
See also