Port Configurations

All Redis Software deployments span multiple physical/virtual nodes. You'll need to keep several ports open between these nodes. This document describes the various port ranges and their uses.

{{< note >}} Whenever you create a new database, you must verify that the ports assigned to the new database's endpoints are open. The cluster will not perform this verification for you. {{< /note >}}

Ports and port ranges used by Redis Software

Redis Software's port usage falls into three general categories:

• Internal: For traffic between or within cluster nodes
• External: For traffic from client applications or external monitoring resources
• Active-Active: For traffic to and from clusters hosting Active-Active databases

Change port configuration

Reserve ports

Redis Software reserves some ports by default (system_reserved_ports). To reserve other ports or port ranges and prevent the cluster from assigning them to database endpoints, configure reserved_ports using one of the following methods:

• [rladmin cluster config]({{< relref "/operate/rs/references/cli-utilities/rladmin/cluster/config" >}})

  shCopy

  rladmin cluster config reserved_ports <list of ports/port ranges>
  

  For example:

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  rladmin cluster config reserved_ports 11000 13000-13010
  

• [Update cluster settings]({{< relref "/operate/rs/references/rest-api/requests/cluster#put-cluster" >}}) REST API request

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  PUT /v1/cluster
  { "reserved_ports": ["list of ports/port ranges"] }
  

  For example:

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  PUT /v1/cluster
  { "reserved_ports": ["11000", "13000-13010"] }
  

Change the Cluster Manager UI port

The Redis Software Cluster Manager UI uses port 8443, by default. You can change this to a custom port as long as the new port is not in use by another process.

To change this port, run:

rladmin cluster config cm_port <custom-port>

After you change the Cluster Manager UI port, use the new port in the URL when accessing the UI on any node in the cluster. Example: https://newnode.mycluster.example.com:<custom-port>

Change the envoy ports

For system health monitoring, Redis uses the following ports by default:

• Port 8002 for envoy admin

• Port 8004 for envoy management server

• Port 8006 for gossip envoy admin

You can change each envoy port to a custom port using the [rladmin cluster config]({{< relref "/operate/rs/references/cli-utilities/rladmin/cluster/config" >}}) command as long as the new port is not in use by another process. When you change envoy_admin_port, expect a restart of envoy.

To change the envoy admin port, run:

$ rladmin cluster config envoy_admin_port <new-port>
Updating envoy_admin_port... restarting now

To change the envoy management server port, run:

$ rladmin cluster config envoy_mgmt_server_port <new-port>
Cluster configured successfully

To change the gossip envoy admin port, run:

$ rladmin cluster config gossip_envoy_admin_port <new-port>
Cluster configured successfully

Change the REST API port

For the REST API, Redis Software uses port 9443 (secure) and port 8080 (not secure), by default. You can change this to a custom port as long as the new port is not in use by another process.

To change these ports, run:

rladmin cluster config cnm_http_port <new-port>

rladmin cluster config cnm_https_port <new-port>

OS conflicts with port 53

{{<embed-md "port-53.md">}}

Update sysctl.conf to avoid port collisions

{{<embed-md "port-collision-avoidance.md">}}

Configure HTTPS

Require HTTPS for API endpoints

By default, the Redis Software API supports communication over HTTP and HTTPS. However, you can turn off HTTP support to ensure that API requests are encrypted.

Before you turn off HTTP support, make sure you migrate any scripts or proxy configurations that use HTTP to the encrypted API endpoint to prevent broken connections.

To turn off HTTP support for API endpoints, run:

rladmin cluster config http_support disabled

After you turn off HTTP support, traffic sent to the unencrypted API endpoint is blocked.

HTTP to HTTPS redirection

Starting with version 6.0.12, you cannot use automatic HTTP to HTTPS redirection. To poll metrics from the metrics_exporter or to access the Cluster Manager UI, use HTTPS in your request. HTTP requests won't be automatically redirected to HTTPS for those services.

Nodes on different VLANs

Nodes in the same cluster must reside on the same VLAN. If you can't host the nodes on the same VLAN, then you must open [all ports]({{< relref "/operate/rs/networking/port-configurations.md" >}}) between them.