# CLUSTER LINKS

```json metadata
{
  "title": "CLUSTER LINKS",
  "description": "Returns a list of all TCP links to and from peer nodes.",
  "categories": ["docs","develop","stack","oss","rs","rc","oss","kubernetes","clients"],
  "syntax_fmt": "CLUSTER LINKS",
  "complexity": "O(N) where N is the total number of Cluster nodes",
  "group": "cluster",
  "command_flags": ["stale"],
  "acl_categories": ["@slow"],
  "since": "7.0.0",
  "arity": 2,
  "tableOfContents": {"sections":[{"id":"examples","title":"Examples"},{"id":"redis-enterprise-and-redis-cloud-compatibility","title":"Redis Enterprise and Redis Cloud compatibility"},{"id":"return-information","title":"Return information"}]}
}
```













Each node in a Redis Cluster maintains a pair of long-lived TCP link with each peer in the cluster: One for sending outbound messages towards the peer and one for receiving inbound messages from the peer.

`CLUSTER LINKS` outputs information of all such peer links as an array, where each array element is a map that contains attributes and their values for an individual link.

## Examples

The following is an example output:

```
> CLUSTER LINKS
1)  1) "direction"
    2) "to"
    3) "node"
    4) "8149d745fa551e40764fecaf7cab9dbdf6b659ae"
    5) "create-time"
    6) (integer) 1639442739375
    7) "events"
    8) "rw"
    9) "send-buffer-allocated"
   10) (integer) 4512
   11) "send-buffer-used"
   12) (integer) 0
2)  1) "direction"
    2) "from"
    3) "node"
    4) "8149d745fa551e40764fecaf7cab9dbdf6b659ae"
    5) "create-time"
    6) (integer) 1639442739411
    7) "events"
    8) "r"
    9) "send-buffer-allocated"
   10) (integer) 0
   11) "send-buffer-used"
   12) (integer) 0
```

Each map is composed of the following attributes of the corresponding cluster link and their values:

1. `direction`: This link is established by the local node `to` the peer, or accepted by the local node `from` the peer.
2. `node`: The node id of the peer.
3. `create-time`: Creation time of the link. (In the case of a `to` link, this is the time when the TCP link is created by the local node, not the time when it is actually established.)
4. `events`: Events currently registered for the link. `r` means readable event, `w` means writable event.
5. `send-buffer-allocated`: Allocated size of the link's send buffer, which is used to buffer outgoing messages toward the peer.
6. `send-buffer-used`: Size of the portion of the link's send buffer that is currently holding data(messages).

## Redis Enterprise and Redis Cloud compatibility

| Redis<br />Enterprise | Redis<br />Cloud | <span style="min-width: 9em; display: table-cell">Notes</span> |
|:----------------------|:-----------------|:------|
| <span title="Not supported">&#x274c; Standard</span><br /><span title="Not supported"><nobr>&#x274c; Active-Active</nobr></span> | <span title="Not supported">&#x274c; Standard</span><br /><span title="Not supported"><nobr>&#x274c; Active-Active</nobr></span> |  |

## Return information

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

[Array reply](../../develop/reference/protocol-spec#arrays): an array of maps where each map contains various attributes and their values of a cluster link.

-tab-sep-

[Array reply](../../develop/reference/protocol-spec#arrays): an array of [Map reply](../../develop/reference/protocol-spec#maps) where each map contains various attributes and their values of a cluster link.