The SYNC command is called by Redis replicas for initiating a replication stream from the master. It has been replaced in newer versions of Redis by PSYNC.

For more information about replication in Redis please check the replication page.

Redis Enterprise and Redis Cloud compatibility

Redis Enterprise	Redis Cloud	Notes
❌ Standard ❌ Active-Active	❌ Standard ❌ Active-Active

Return information

RESP2 RESP3

Non-standard return value, a bulk transfer of the data followed by PING and write requests from the master.