The rebalance policy for balancing node capacity is performed only within the same availability zone and does not transfer data across availability zones. Even if the storage space in an availability zone is exhausted, the replica will not be migrated to other zones. However, in specific situations, cross-domain transmission ensures topology security. For example, in situations such as node migration or topology configuration repair, if all three replicas are located in the same availability zone, you can migrate one of the replicas to another zone.
In an active-active cluster, the replica of template volumes follows the principle of balanced distribution, meaning each availability zone contains nodes that store a nearly equal number of volume replicas (with a difference not exceeding 4 data blocks, which is equivalent to 1 GiB). There are no requirements for the distribution of replication factors across different availability zones.
