{
  "id": "manage",
  "title": "Manage Active-Active databases",
  "url": "https://redis.io/docs/latest/operate/rs/7.8/databases/active-active/manage/",
  "summary": "Manage your Active-Active database settings.",
  "content": "\nYou can configure and manage your Active-Active database from either the Cluster Manager UI or the command line.\n\nTo change the global configuration of the Active-Active database, use [`crdb-cli`]().\n\nIf you need to apply changes locally to one database instance, you use the Cluster Manager UI or [`rladmin`]().\n\n## Database settings\n\nMany Active-Active database settings can be changed after database creation. One notable exception is database clustering. Database clustering can't be turned on or off after the database has been created.\n\n## Participating clusters\n\nYou can add and remove participating clusters of an Active-Active database to change the topology.\nTo manage the changes to Active-Active topology, use [`crdb-cli`]() or the participating clusters list in the Cluster Manager UI.\n\n### Add participating clusters\n\nAll existing participating clusters must be online and in a syncing state when you add new participating clusters.\n\nNew participating clusters create the Active-Active database instance based on the global Active-Active database configuration.\nAfter you add new participating clusters to an existing Active-Active database,\nthe new database instance can accept connections and read operations.\nThe new instance does not accept write operations until it is in the syncing state.\n\n\nIf an Active-Active database [runs on flash memory](), you cannot add participating clusters that run on RAM only.\n\n\nTo add a new participating cluster to an existing Active-Active configuration using the Cluster Manager UI:\n\n1. Select the Active-Active database from the **Databases** list and go to its **Configuration** screen.\n\n1. Click **Edit**.\n\n1. In the **Participating clusters** section, go to **Other participating clusters** and click **+ Add cluster**.\n\n1. In the **Add cluster** configuration panel, enter the new cluster's URL, port number, and the admin username and password for the new participating cluster:\n\n    \n\n1. Click **Join cluster** to add the cluster to the list of participating clusters. \n\n1. Click **Save**.\n\n\n### Remove participating clusters\n\nAll existing participating clusters must be online and in a syncing state when you remove an online participating cluster.\nIf you must remove offline participating clusters, you can forcefully remove them.\nIf a forcefully removed participating cluster tries to rejoin the cluster,\nits Active-Active database membership will be out of date.\nThe joined participating clusters reject updates sent from the removed participating cluster.\nTo prevent rejoin attempts, purge the forcefully removed instance from the participating cluster.\n\nTo remove a participating cluster using the Cluster Manager UI:\n\n1. Select the Active-Active database from the **Databases** list and go to its **Configuration** screen.\n\n1. Click **Edit**.\n\n1. In the **Participating clusters** section, point to the cluster you want to delete in the **Other participating clusters** list:\n\n    \n\n1. Click  to remove the cluster.\n\n1. Click **Save**.\n\n## Replication backlog\n\nRedis databases that use [replication for high availability]() maintain a replication backlog (per shard) to synchronize the primary and replica shards of a database. In addition to the database replication backlog, Active-Active databases maintain a backlog (per shard) to synchronize the database instances between clusters.\n\nBy default, both the database and Active-Active replication backlogs are set to one percent (1%) of the database size divided by the number of shards. This can range between 1MB to 250MB per shard for each backlog.\n\n### Change the replication backlog size\n\nUse the [`crdb-cli`]() utility to control the size of the replication backlogs. You can set it to `auto` or set a specific size.  \n\nUpdate the database replication backlog configuration with the `crdb-cli` command shown below.\n\n```text\ncrdb-cli crdb update --crdb-guid \u003ccrdb_guid\u003e --default-db-config \"{\\\"repl_backlog_size\\\": \u003csize in MB | 'auto'\u003e}\"\n```\n\nUpdate the Active-Active (CRDT) replication backlog with the command shown below: \n\n```text\ncrdb-cli crdb update --crdb-guid \u003ccrdb_guid\u003e --default-db-config \"{\\\"crdt_repl_backlog_size\\\": \u003csize in MB | 'auto'\u003e}\"\n```\n\n## Data persistence\n\nActive-Active supports AOF (Append-Only File) data persistence only.  Snapshot persistence is _not_ supported for Active-Active databases and should not be used.\n\nIf an Active-Active database is currently using snapshot data persistence, use `crdb-cli` to switch to AOF persistence:\n```text\n crdb-cli crdb update --crdb-guid \u003cCRDB_GUID\u003e --default-db-config '{\"data_persistence\": \"aof\", \"aof_policy\":\"appendfsync-every-sec\"}'\n```\n\n\n",
  "tags": ["docs","operate","rs"],
  "last_updated": "2026-04-01T08:10:08-05:00"
}