If a TSA failure takes place in a region with Master caches, upon recovery the Master caches cannot automatically force a resynchronization of all live Replicas across the WAN, because that could result in data loss. In this case, when an entire region is down (for example, your data center is offline), you must use a manual recovery process. You will need to designate new Master caches, update the configuration, and restart the Orchestrators.

In preparation for disaster recovery, two Orchestrator configurations should be ready:

If Region A goes down, then Configuration 2 can be applied in Region B. Ideally, Region B would already be serving as a read-only or backup region. When Region B becomes the Master, it can then be used to resynchronize Region A.