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How to Install Redis® on Rocky Linux 9

Rocky LinuxRedis®
HJ
Updated on November 21, 2023
How to Install Redis® on Rocky Linux 9 header image

Introduction

Redis® is an open-source, in-memory data store used as a database, cache, and message broker. Redis® is known for its high performance and supports multiple data structures such as strings, hashes, lists, and sets. It's widely used in real-time applications for caching, session management, and analytics. By keeping data in memory, Redis® offers lightning-fast data retrieval ideal for applications that require quick response times.

This article explains how to install Redis® on Rocky Linux 9.

Prerequisites

Before you begin:

Install Redis®

Redis® is available in the default package repositories on Rocky Linux 9. Follow the steps below to install Redis® and enable application service to automatically start at system boot.

  1. Install Redis®.

    console 
    $ sudo dnf install redis

  2. Enable the Redis® service to automatically start at system boot.

    console 
    $ sudo systemctl enable redis

  3. Start the Redis® service.

    console 
    $ sudo systemctl start redis

  4. View the Redis® service status and verify that's active and running on your server.

    console 
    $ sudo systemctl status redis

    Output:

    ● redis.service - Redis® persistent key-value database
     Loaded: loaded (/usr/lib/systemd/system/redis.service; enabled; preset: disabled)
    Drop-In: /etc/systemd/system/redis.service.d
             └─limit.conf
     Active: active (running) since Wed 2024-07-24 05:39:18 UTC; 57s ago
   Main PID: 5219 (redis-server)
     Status: "Ready to accept connections"
      Tasks: 5 (limit: 11074)
     Memory: 7.3M
        CPU: 123ms
     CGroup: /system.slice/redis.service
             └─5219 "/usr/bin/redis-server 127.0.0.1:6379"

  5. Test access to the Redis® server to verify that it responds to CLI requests.

    console 
    $ redis-cli ping

    Output:

    PONG

Configure Redis®

Redis® uses the /etc/redis/redis.conf main configuration to run on your server with specific settings. Follow the steps below to verify the default configuration information and configure Redis® on your server.

  1. Open the main Redis® configuration file using a text editor such as nano.

    console 
    $ sudo nano /etc/redis/redis.conf

  2. Find the following configuration directives and uncomment each option to match your needs.

    ini 
    bind 127.0.0.1 -::1
port 6379
daemonize yes
protected-mode yes
maxmemory 256mb
maxmemory-policy allkeys-lru
tcp-keepalive 300
loglevel notice
logfile /var/log/redis/redis.log

    Save and close the file.

    Within the above configuration:

    • bind: Enables Redis® to listen for connections using both IPv4 127.0.0.1 and IPv6 ::1 loopback addresses to restrict external access to the server.
    • port: Enables Redis® to listen for client connection requests on a specific TCP port such as 6379.
    • daemonize: When set to yes, Redis® runs in the background as a daemon process while false disables background processes.
    • protected-mode: Disables remote access to the Redis® server when enabled to only accept localhost connections.
    • maxmemory: Sets the maximum amount of memory Redis® can use. For example, 256 megabytes. When the limit is reached, Redis® removes old data based on the specified eviction policy.
    • maxmemory-policy: Sets the Redis® eviction policy to clear the least recently used data from memory when the maximum memory limit is reached. Common policies include volatile-lru, allkeys-lru, volatile-random, allkeys-random, and noeviction that apply to all keys on the server.
    • tcp-keepalive: Configures Redis® to send keep-alive packets over idle TCP connections every 300 seconds to detect and close dormant connections.
    • loglevel: Sets the amount of logging information on the Redis® server. When set to notice, Redis® logs significant events, such as start and stop messages, configuration changes, and errors to balance between detail and conciseness for troubleshooting purposes.
    • logfile: Specifies the file where Redis® will write its log messages.

  3. Restart the Redis® service to apply your configuration changes.

    console 
    $ sudo systemctl restart redis

Secure Redis®

Password authentication adds an extra layer of protection on a Redis® server to ensure that only authorized users can execute commands and access stored data. Follow the steps below to secure the Redis® with password authentication and block unauthorized client connections on the server.

  1. Open the main Redis® configuration file to enable authentication.

    console 
    $ sudo nano /etc/redis/redis.conf

  2. Find the requirepass directive and replace the default foobared value with a strong password of your choice.

    INI 
    requirepass your_secure_password

    Save and close the file.

  3. Restart the Redis® service to apply your configuration changes.

    console 
    $ sudo systemctl restart redis

Access Redis®

Follow the steps below to access the Redis®, test your authentication and create sample keys on the server.

  1. Access the Redis® CLI.

    console 
    $ redis-cli

    Your output should be similar to the one below when successful.

    127.0.0.1:6379>

  2. Authenticate with your password to access the Redis® console. Replace your_secure_password with the actual password you set earlier.

    console 
    127.0.0.1:6379> AUTH your_secure_password

    Output.

    OK

  3. Create a new sample key mykey with the value Greetings from Vultr.

    console 
    127.0.0.1:6379> set mykey Greetings from Vultr

  4. Get the stored mykey value.

    console 
    127.0.0.1:6379> get mykey

    Output:

    "Greetings from Vultr"

Conclusion

You have installed Redis® on Rocky Linux 9 and enabled password authentication to secure the server. Redis® works as an in-memory data store you can integrate with your existing applications to enable caching. For more information and additional security options, visit the Redis® documentation.