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SSUBSCRIBE

content/commands/ssubscribe.md

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Subscribes the client to the specified shard channels.

In a Redis cluster, shard channels are assigned to slots by the same algorithm used to assign keys to slots. Client(s) can subscribe to a node covering a slot (primary/replica) to receive the messages published. All the specified shard channels needs to belong to a single slot to subscribe in a given SSUBSCRIBE call, A client can subscribe to channels across different slots over separate SSUBSCRIBE call.

For more information about sharded Pub/Sub, see [Sharded Pub/Sub]({{< relref "/develop/pubsub#sharded-pubsub" >}}).

Examples

> ssubscribe orders
Reading messages... (press Ctrl-C to quit)
1) "ssubscribe"
2) "orders"
3) (integer) 1
1) "smessage"
2) "orders"
3) "hello"

Redis Software and Redis Cloud compatibility

| Redis Software | Redis Cloud | <span style="min-width: 9em; display: table-cell">Notes</span> | |:----------------------|:-----------------|:------| | <span title="Supported">✅ Standard</span> <span title="Supported"><nobr>✅ Active-Active</nobr></span> | <span title="Supported">✅ Standard</span> <span title="Supported"><nobr>✅ Active-Active</nobr></span> | |

Return information

{{< multitabs id="ssubscribe-return-info" tab1="RESP2" tab2="RESP3" >}}

When successful, this command doesn't return anything. Instead, for each shard channel, one message with the first element being the string ssubscribe is pushed as a confirmation that the command succeeded. Note that this command can also return a -MOVED redirect.

-tab-sep-

When successful, this command doesn't return anything. Instead, for each shard channel, one message with the first element being the string 'ssubscribe' is pushed as a confirmation that the command succeeded. Note that this command can also return a -MOVED redirect.

{{< /multitabs >}}