Redis 6

Description

Redis 6 available as container, is an advanced key-value store. It is often referred to as a data structure server since keys can contain strings, hashes, lists, sets and sorted sets. You can run atomic operations on these types, like appending to a string; incrementing the value in a hash; pushing to a list; computing set intersection, union and difference; or getting the member with highest ranking in a sorted set. In order to achieve its outstanding performance, Redis works with an in-memory dataset. Depending on your use case, you can persist it either by dumping the dataset to disk every once in a while, or by appending each command to a log.

Usage

For this, we will assume that you are using the rhel8/redis-6 image. If you want to set only the mandatory environment variables and not store the database in a host directory, execute the following command:

$ podman run -d --name redis_database -p 6379:6379 rhel8/redis-6

This will create a container named redis_database. Port 6379 will be exposed and mapped to the host.

If you want your database to be persistent across container executions, also add a -v /host/db/path:/var/lib/redis/data:Z argument. This will be the Redis data directory.

For protecting Redis data by a password, pass REDIS_PASSWORD environment variable to the container like this:

$ podman run -d --name redis_database -e REDIS_PASSWORD=strongpassword rhel8/redis-6

Warning: since Redis is pretty fast an outside user can try up to 150k passwords per second against a good box. This means that you should use a very strong password otherwise it will be very easy to break.

Environment variables and volumes

REDIS_PASSWORD
Password for the server access

You can also set the following mount points by passing the -v /host:/container:Z flag to podman.

/var/lib/redis/data
Redis data directory

Notice: When mouting a directory from the host into the container, ensure that the mounted directory has the appropriate permissions and that the owner and group of the directory matches the user UID or name which is running inside the container.

Troubleshooting

Redis logs into standard output, so the log is available in the container log. The log can be examined by running:

podman logs <container>

See also

Dockerfile and other sources for this container image are available on https://github.com/sclorg/redis-container. In that repository you also can find another versions of Python environment Dockerfiles. Dockerfile for CentOS is called Dockerfile, Dockerfile for RHEL7 is called Dockerfile.rhel7, for RHEL8 it's Dockerfile.rhel8 and the Fedora Dockerfile is called Dockerfile.fedora.