Replication collisions

With an active/active link, clients can make configuration changes and changes to namespace content on both HCP systems involved in the link. This situation can result in configuration and content collisions.

With an active/passive link, if clients are allowed to make changes on both HCP systems involved in the link while the link is failed over to the replica, configuration and content collisions can occur on failback. Collisions can also occur on failback if changes made on the replica while a link is failed over conflict with configuration or content that was not yet replicated at the time of failover.

The way HCP handles collisions that occur due to replication depends on the type of collision. The general rule for namespace content is that more recent changes have priority over conflicting less recent changes. If conflicting changes occur at exactly the same time, HCP gives priority to the change that occurred on the system on which the link was created.

When configuration changes result in a conflict, the replication service pauses replication or recovery of the tenant, as applicable. For more information on conflicting configuration changes, see Automatically paused tenant replication or recovery.

Note: If the system time is not in sync on the two systems involved in a replication link, replication collision handling may have unexpected results.

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