[id='xsite_sync_backups-{context}']
= Synchronous Backups
When {brandname} replicates data to backup locations, it waits until the
operation completes before writing to the local cache.

You can control how {brandname} handles writes to the local cache if backup
operations fail. For example, you can configure {brandname} to attempt to abort
local writes and throw exceptions if backups to remote sites fail.

Synchronous backups also support two-phase commits with caches that participate
in optimistic transactions. The first phase of the backup acquires a lock. The
second phase commits the modification.

[IMPORTANT]
====
Two-phase commit with cross-site replication has a significant performance
impact because it requires two round-trips across the network.
====
