# PSYNC Initiates a replication stream from the master. The `PSYNC` command is called by Redis replicas for initiating a replication stream from the master. For more information about replication in Redis please check the [replication page](https://redis.io/docs/latest/operate/oss_and_stack/management/replication). ## Return information {{< multitabs id="psync-return-info" tab1="RESP2" tab2="RESP3" >}} **Non-standard return value**, a bulk transfer of the data followed by `PING` and write requests from the master. -tab-sep- **Non-standard return value**, a bulk transfer of the data followed by `PING` and write requests from the master.