Configuration

Requirements

Synchronous replication requires an operational ArangoDB cluster.

Enabling synchronous replication

Synchronous replication can be enabled per collection. When creating acollection you may specify the number of replicas using thereplicationFactor parameter. The default value is set to 1 whicheffectively disables synchronous replication.

Example:

127.0.0.1:8530@_system> db._create("test", {"replicationFactor": 3})

In the above case, any write operation will require 2 replicas toreport success from now on.

Preparing growth

You may create a collection with higher replication factor thanavailable. When additional db servers become available the shards areautomatically replicated to the newly available machines.

Multiple replicas of the same shard can never coexist on the same dbserver instance.