Manage Chained Replication
Starting in version 2.0, MongoDB supports chained replication. A chained replication occurs when a secondary member replicates from another secondary member instead of from the primary. This might be the case, for example, if a secondary selects its replication target based on ping time and if the closest member is another secondary.
Chained replication can reduce load on the primary. But chained replication can also result in increased replication lag, depending on the topology of the network.
MongoDB enables chained replication by default. This procedure describes how to disable it and how to re-enable it.
If chained replication is disabled, you still can use
replSetSyncFrom to specify that a secondary replicates from another secondary. But that configuration will last only until the secondary recalculates which member to sync from.
You can use the following sequence of commands to set
Copy the configuration settings into the
Take note of whether the current configuration settings contain the
settingsembedded document. If they do, skip this step.
To avoid data loss, skip this step if the configuration settings contain the
If the current configuration settings do not contain the
settingsembedded document, create the embedded document by issuing the following command:
Issue the following sequence of commands to set
To re-enable chained replication, set
true. You can use the following sequence of commands: