bitnami-containers/bitnami/redis-cluster

Bitnami package for Redis® Cluster

What is Redis® Cluster?

Redis® is an open source, scalable, distributed in-memory cache for applications. It can be used to store and serve data in the form of strings, hashes, lists, sets and sorted sets.

Overview of Redis® Cluster Disclaimer: Redis is a registered trademark of Redis Ltd. Any rights therein are reserved to Redis Ltd. Any use by Bitnami is for referential purposes only and does not indicate any sponsorship, endorsement, or affiliation between Redis Ltd.

TL;DR

docker run --name redis-cluster -e ALLOW_EMPTY_PASSWORD=yes bitnami/redis-cluster:latest

Docker Compose

curl -sSL https://raw.githubusercontent.com/bitnami/containers/main/bitnami/redis-cluster/docker-compose.yml > docker-compose.yml
docker-compose up -d

Why use Bitnami Images?

• Bitnami closely tracks upstream source changes and promptly publishes new versions of this image using our automated systems.
• With Bitnami images the latest bug fixes and features are available as soon as possible.
• Bitnami containers, virtual machines and cloud images use the same components and configuration approach - making it easy to switch between formats based on your project needs.
• All our images are based on minideb -a minimalist Debian based container image that gives you a small base container image and the familiarity of a leading Linux distribution- or scratch -an explicitly empty image-.
• All Bitnami images available in Docker Hub are signed with Docker Content Trust (DCT). You can use DOCKER_CONTENT_TRUST=1 to verify the integrity of the images.
• Bitnami container images are released on a regular basis with the latest distribution packages available.

Looking to use Redis® Cluster in production? Try VMware Tanzu Application Catalog, the enterprise edition of Bitnami Application Catalog.

How to deploy Redis(R) Cluster in Kubernetes?

Deploying Bitnami applications as Helm Charts is the easiest way to get started with our applications on Kubernetes. Read more about the installation in the Bitnami Redis(R) Cluster Chart GitHub repository.

Bitnami containers can be used with Kubeapps for deployment and management of Helm Charts in clusters.

Supported tags and respective Dockerfile links

Learn more about the Bitnami tagging policy and the difference between rolling tags and immutable tags in our documentation page.

You can see the equivalence between the different tags by taking a look at the tags-info.yaml file present in the branch folder, i.e bitnami/ASSET/BRANCH/DISTRO/tags-info.yaml.

Subscribe to project updates by watching the bitnami/containers GitHub repo.

Get this image

The recommended way to get the Bitnami Redis(R) Cluster Docker Image is to pull the prebuilt image from the Docker Hub Registry.

docker pull bitnami/redis-cluster:latest

To use a specific version, you can pull a versioned tag. You can view the list of available versions in the Docker Hub Registry.

docker pull bitnami/redis-cluster:[TAG]

If you wish, you can also build the image yourself by cloning the repository, changing to the directory containing the Dockerfile and executing the docker build command. Remember to replace the APP, VERSION and OPERATING-SYSTEM path placeholders in the example command below with the correct values.

git clone https://github.com/bitnami/containers.git
cd bitnami/APP/VERSION/OPERATING-SYSTEM
docker build -t bitnami/APP:latest .

Persisting your application

If you remove the container all your data will be lost, and the next time you run the image the database will be reinitialized. To avoid this loss of data, you should mount a volume that will persist even after the container is removed.

For persistence you should mount a directory at the /bitnami path. If the mounted directory is empty, it will be initialized on the first run.

docker run \
    -e ALLOW_EMPTY_PASSWORD=yes
    -v /path/to/redis-cluster-persistence:/bitnami \
    bitnami/redis-cluster:latest

You can also do this with a minor change to the docker-compose.yml file present in this repository:

redis-cluster:
  ...
  volumes:
    - /path/to/redis-cluster-persistence:/bitnami
  ...

Connecting to other containers

Using Docker container networking, a different server running inside a container can easily be accessed by your application containers and vice-versa.

Containers attached to the same network can communicate with each other using the container name as the hostname.

Using the Command Line

Step 1: Create a network

docker network create redis-cluster-network --driver bridge

Step 2: Launch the Redis(R) Cluster container within your network

Use the --network <NETWORK> argument to the docker run command to attach the container to the redis-cluster-network network.

docker run -e ALLOW_EMPTY_PASSWORD=yes --name redis-cluster-node1 --network redis-cluster-network bitnami/redis-cluster:latest

Step 3: Run another containers

We can launch another containers using the same flag (--network NETWORK) in the docker run command. If you also set a name to your container, you will be able to use it as hostname in your network.

Configuration

Configuration file

The image looks for configurations in /opt/bitnami/redis/mounted-etc/redis.conf. You can overwrite the redis.conf file using your own custom configuration file.

docker run --name redis \
    -e ALLOW_EMPTY_PASSWORD=yes \
    -v /path/to/your_redis.conf:/opt/bitnami/redis/mounted-etc/redis.conf \
    -v /path/to/redis-data-persistence:/bitnami/redis/data \
    bitnami/redis-cluster:latest

Alternatively, modify the docker-compose.yml file present in this repository:

services:
  redis-node-0:
  ...
    volumes:
      - /path/to/your_redis.conf:/opt/bitnami/redis/mounted-etc/redis.conf
      - /path/to/redis-persistence:/bitnami/redis/data
  ...

Refer to the Redis(R) configuration manual for the complete list of configuration options.

Overriding configuration

Instead of providing a custom redis.conf, you may also choose to provide only settings you wish to override. The image will look for /opt/bitnami/redis/mounted-etc/overrides.conf. This will be ignored if custom redis.conf is provided.

docker run --name redis \
    -e ALLOW_EMPTY_PASSWORD=yes \
    -v /path/to/overrides.conf:/opt/bitnami/redis/mounted-etc/overrides.conf \
    bitnami/redis:latest

Alternatively, modify the docker-compose.yml file present in this repository:

services:
  redis:
  ...
    volumes:
      - /path/to/overrides.conf:/opt/bitnami/redis/mounted-etc/overrides.conf
  ...

Environment variables

The following env vars are supported for this container:

Name	Description
REDIS_DISABLE_COMMANDS	Disables the specified Redis(R) commands
REDIS_PORT_NUMBER	Set the Redis(R) port. Default=: 6379
REDIS_PASSWORD	Set the Redis(R) password. Default: bitnami
ALLOW_EMPTY_PASSWORD	Enables access without password
REDIS_DNS_RETRIES	Number of retries to get the IPs of the provided REDIS_NODES. It will wait 5 seconds between retries
REDISCLI_AUTH	Provide the same value as the configured REDIS_PASSWORD for the redis-cli tool to authenticate
REDIS_CLUSTER_CREATOR	Set to yes if the container will be the one on charge of initialize the cluster. This node will also be part of the cluster.
REDIS_CLUSTER_REPLICAS	Number of replicas for every master that the cluster will have.
REDIS_NODES	String delimited by spaces containing the hostnames of all of the nodes that will be part of the cluster
REDIS_CLUSTER_ANNOUNCE_IP	IP that the node should announce, used for non dynamic ip environments
REDIS_CLUSTER_ANNOUNCE_PORT	Port that the node should announce, used for non dynamic ip environments.
REDIS_CLUSTER_ANNOUNCE_HOSTNAME	Hostname that node should announce, used for non dynamic ip environments.
REDIS_CLUSTER_PREFERRED_ENDPOINT_TYPE	Preferred endpoint type which cluster should use, options- ip, hostname
REDIS_CLUSTER_ANNOUNCE_BUS_PORT	The cluster bus port to announce.
REDIS_CLUSTER_DYNAMIC_IPS	Set to no if your Redis(R) cluster will be created with statical IPs. Default: yes
REDIS_TLS_ENABLED	Whether to enable TLS for traffic or not. Defaults to no.
REDIS_TLS_PORT_NUMBER	Port used for TLS secure traffic. Defaults to 6379.
REDIS_TLS_CERT_FILE	File containing the certificate file for the TLS traffic. No defaults.
REDIS_TLS_KEY_FILE	File containing the key for certificate. No defaults.
REDIS_TLS_CA_FILE	File containing the CA of the certificate. No defaults.
REDIS_TLS_DH_PARAMS_FILE	File containing DH params (in order to support DH based ciphers). No defaults.
REDIS_TLS_AUTH_CLIENTS	Whether to require clients to authenticate or not. Defaults to yes.
REDIS_CLUSTER_SLEEP_BEFORE_DNS_LOOKUP	Number of seconds to wait before initializing the cluster. Set this to a higher value if you sometimes have issues with initial cluster creation. Defaults to 0.
REDIS_CLUSTER_DNS_LOOKUP_RETRIES	Number of retries for the node's DNS lookup during the initial cluster creation. Defaults to 5.
REDIS_CLUSTER_DNS_LOOKUP_SLEEP	Number of seconds to wait between each node's DNS lookup during the initial cluster creation. Defaults to 1.
REDIS_IO_THREADS	Number of threads to implement multithreading operations. Defaults to 1.
REDIS_IO_THREADS_DO_READS	Enables multithreading for read operations. Defaults to false.
REDIS_RDB_POLICY	Set this variable to enable RDB persistent storage RDB data synchronization strategy configuration example 900#1 300#10 60#1000 Defaults to disable RDB persistent storage.
REDIS_RDB_POLICY_DISABLED	If set to yes the container will skip the configuration of RDB policy ('save' setting) and rely on Redis(R) default. If REDIS_RDB_POLICY is provided, this will be ignored. Defaults to no.

Once all the Redis(R) nodes are running you need to execute command like the following to initiate the cluster:

redis-cli --cluster create node1:port node2:port --cluster-replicas 1 --cluster-yes

Where you can add all the node:port that you want. The --cluster-replicas parameters indicates how many replicas you want to have for every master.

Cluster Initialization Troubleshooting

Depending on the environment you're deploying into, you might run into issues where the cluster initialization is not completing successfully. One of the issue is related to the DNS lookup of the redis nodes performed during cluster initialization. By default, this DNS lookup is performed as soon as all the redis nodes reply to a successful ping. However, in some environments such as Kubernetes, it can help to wait some time before performing this DNS lookup in order to prevent getting stale records. To this end, you can increase REDIS_CLUSTER_SLEEP_BEFORE_DNS_LOOKUP to a value around 30 which has been found to be good in most cases.

Securing Redis(R) Cluster traffic

Starting with version 6, Redis(R) adds the support for SSL/TLS connections. Should you desire to enable this optional feature, you may use the aforementioned REDIS_TLS_* environment variables to configure the application.

When enabling TLS, conventional standard traffic is disabled by default. However this new feature is not mutually exclusive, which means it is possible to listen to both TLS and non-TLS connection simultaneously. To enable non-TLS traffic, set REDIS_TLS_PORT_NUMBER to another port different than 0.

1. Using docker run

   $ docker run --name redis-cluster \
       -v /path/to/certs:/opt/bitnami/redis/certs \
       -v /path/to/redis-cluster-persistence:/bitnami \
       -e ALLOW_EMPTY_PASSWORD=yes \
       -e REDIS_TLS_ENABLED=yes \
       -e REDIS_TLS_CERT_FILE=/opt/bitnami/redis/certs/redis.crt \
       -e REDIS_TLS_KEY_FILE=/opt/bitnami/redis/certs/redis.key \
       -e REDIS_TLS_CA_FILE=/opt/bitnami/redis/certs/redisCA.crt \
       bitnami/redis-cluster:latest
   

2. Modifying the docker-compose.yml file present in this repository:

     redis-cluster:
     ...
       environment:
         ...
         - REDIS_TLS_ENABLED=yes
         - REDIS_TLS_CERT_FILE=/opt/bitnami/redis/certs/redis.crt
         - REDIS_TLS_KEY_FILE=/opt/bitnami/redis/certs/redis.key
         - REDIS_TLS_CA_FILE=/opt/bitnami/redis/certs/redisCA.crt
       ...
       volumes:
         - /path/to/certs:/opt/bitnami/redis/certs
       ...
     ...
   

Alternatively, you may also provide with this configuration in your custom configuration file.

Logging

The Bitnami Redis(R) Cluster Docker image sends the container logs to stdout. To view the logs:

docker logs redis-cluster

You can configure the containers logging driver using the --log-driver option if you wish to consume the container logs differently. In the default configuration docker uses the json-file driver.

Maintenance

Upgrade this image

Bitnami provides up-to-date versions of Redis(R) Cluster, including security patches, soon after they are made upstream. We recommend that you follow these steps to upgrade your container.

Step 1: Get the updated image

docker pull bitnami/redis-cluster:latest

Step 2: Stop the running container

Stop the currently running container using the command

docker stop redis-cluster

Step 3: Remove the currently running container

docker rm -v redis-cluster

Step 4: Run the new image

Re-create your container from the new image.

docker run --name redis-cluster bitnami/redis-cluster:latest

Upgrading

To 5.0.12-debian-10-r48 release, 6.2.1-debian-10-r48 release , 6.0.12-debian-10-r48

The cluster initialization logic has changed. Now the container in charge of initialize the cluster will also be part of the cluster. It will initialize Redis in background, create the cluster and then bring back to foreground the Redis process.

Contributing

We'd love for you to contribute to this container. You can request new features by creating an issue or submitting a pull request with your contribution.

Issues

If you encountered a problem running this container, you can file an issue. For us to provide better support, be sure to fill the issue template.

License

Copyright © 2023 VMware, Inc.

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.