(Last Updated On: January 10, 2019)

In this tutorial, we will cover step by step ways to install Redis on CentOS 7. Redis is an Open Source in-memory data structure store. Redis can be used as a database server, as a message broker or for caching data in memory for faster retrieval.  Among the data structures supported by Redis are:

  • Hashes
  • sets with range queries
  • Strings
  • sorted lists
  • Hyperloglogs
  • Bitmaps
  • Geospatial indexes e.t.c

For Ubuntu 18.04 / Debian 9, use:

How to Install Redis on Ubuntu 18.04 / Debian 9

For RHEL 8, use:

Install and Configure Redis Server on RHEL 8 / CentOS 8

How to Install Redis on CentOS 7

In this section, we will look at how to install the latest release of Redis on CentOS 7.

Step 1: Update your CentOS 7

Ensure your system is updated before installing Redis

sudo yum -y update

Step 2: Add REMI repisitory

The latest version of Redis is available on Remi repository, add it by executing the command:

sudo yum -y install http://rpms.remirepo.net/enterprise/remi-release-7.rpm

Step 3: Install Redis on CentOS 7

After adding the repository, install latest Redis on CentOS 7 from the repository.

$ sudo yum --enablerepo=remi install redis
Loaded plugins: fastestmirror, ovl
Loading mirror speeds from cached hostfile
base: centos.mirrors.proxad.net
epel: mirrors.ircam.fr
extras: centos.crazyfrogs.org
remi: remi.mirror.ate.info
remi-php72: remi.mirror.ate.info
remi-safe: remi.mirror.ate.info
updates: centos.quelquesmots.fr
rabbitmq_rabbitmq-server/x86_64/signature | 836 B 00:00:00
rabbitmq_rabbitmq-server/x86_64/signature | 1.0 kB 00:00:00 !!!
rabbitmq_rabbitmq-server-source/signature | 836 B 00:00:00
rabbitmq_rabbitmq-server-source/signature | 1.0 kB 00:00:00 !!!
Resolving Dependencies
--> Running transaction check
---> Package redis.x86_64 0:5.0.3-1.el7.remi will be installed
--> Finished Dependency Resolution
Dependencies Resolved
=======================================================================================================================================================
Package Arch Version Repository Size
Installing:
redis x86_64 5.0.3-1.el7.remi remi 919 k
Transaction Summary
Install 1 Package
Total download size: 919 k
Installed size: 3.0 M
Is this ok [y/d/N]: y
Downloading packages:
redis-5.0.3-1.el7.remi.x86_64.rpm | 919 kB 00:00:00
Running transaction check
Running transaction test
Transaction test succeeded
Running transaction
Installing : redis-5.0.3-1.el7.remi.x86_64 1/1
Verifying : redis-5.0.3-1.el7.remi.x86_64 1/1
Installed:
redis.x86_64 0:5.0.3-1.el7.remi
Complete!

Get more package details from:

$ rpm -qi redis 
Name : redis
Version : 5.0.3
Release : 1.el7.remi
Architecture: x86_64
Install Date: Thu 10 Jan 2019 05:02:04 PM EAT
Group : Applications/Databases
Size : 3155665
License : BSD
Signature : DSA/SHA1, Wed 12 Dec 2018 04:44:08 PM EAT, Key ID 004e6f4700f97f56
Source RPM : redis-5.0.3-1.el7.remi.src.rpm
Build Date : Wed 12 Dec 2018 04:42:35 PM EAT
Build Host : builder.remirepo.net
Relocations : (not relocatable)
Packager : https://blog.remirepo.net/
Vendor : Remi Collet
URL : http://redis.io
Bug URL : https://forum.remirepo.net/
Summary : A persistent key-value database
Description :
Redis 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.
Redis also supports trivial-to-setup master-slave replication, with very
fast non-blocking first synchronization, auto-reconnection on net split
and so forth.
Other features include Transactions, Pub/Sub, Lua scripting, Keys with a
limited time-to-live, and configuration settings to make Redis behave like
a cache.
You can use Redis from most programming languages also.

Step 3: Start Redis Service on CentOS 7

Redis service can be started on CentOS 7 using systemd service manager. Also, enable the service to start on system boot.

sudo systemctl enable --now redis

Step 4: Enable network Listen for Redis Service

For network clients to connect to your Redis server, it needs the service to listen on a network IP Address.

Open the file /etc/redis.conf with your favorite text editor

sudo vim /etc/redis.conf

Then change line 61 bind 127.0.0.1 to below:

bind 0.0.0.0

Configure Redis Authentication – (Optional but recommended)

Configure Redis Authentication for clients to require AUTH <PASSWORD> before processing any other commands.

requirepass  <AuthPassword>

Example:

requirepass oobaiY8

Set Persistent Store for Recovery

Set persistence mode by changing the appendonlyvalue to yes

appendonly yes
appendfilename "appendonly.aof"

Restart redis service after making the changes

sudo systemctl restart redis

Check redis service status:

$ sudo systemctl status  redis
● redis.service - Redis persistent key-value database
   Loaded: loaded (/usr/lib/systemd/system/redis.service; enabled; vendor preset: disabled)
  Drop-In: /etc/systemd/system/redis.service.d
           └─limit.conf
   Active: active (running) since Tue 2018-12-04 15:23:08 UTC; 3s ago
  Process: 3625 ExecStop=/usr/libexec/redis-shutdown (code=exited, status=0/SUCCESS)
 Main PID: 3640 (redis-server)
   CGroup: /system.slice/redis.service
           └─3640 /usr/bin/redis-server 0.0.0.0:6379

Dec 04 15:23:08 cent-01 systemd[1]: Starting Redis persistent key-value database...
Dec 04 15:23:08 cent-01 systemd[1]: Started Redis persistent key-value database.

You can view the port and IP used by Redis service using the sscommand:

$ sudo ss -tunelp | grep 6379
tcp LISTEN 0 128 *:6379  *:*  users:(("redis-server",pid=28163,fd=4)) uid:995 ino:305

If you have an active firewalld service, allow port 6379

sudo firewall-cmd --add-port=6379/tcp --permanenent
sudo firewall-cmd --reload

Step 5: Test connection to Redis Server

Confirm that you can connect to redis locally:

$ redis-cli
127.0.0.1:6379>

Test authenticate:

127.0.0.1:6379> AUTH <AuthPassword>
OK

You should receive OK in the output. If you input a wrong password, Authentication should fail:

127.0.0.1:6379> AUTH WrongPassword
(error) ERR invalid password

Check redis information.

127.0.0.1:6379>  INFO

This will output a long list of data. You can limit the output by passing Section as an argument. E.g.

127.0.0.1:6379> INFO Server
# Server
redis_version:3.2.12
redis_git_sha1:00000000
redis_git_dirty:0
redis_build_id:7897e7d0e13773f
redis_mode:standalone
os:Linux 3.10.0-862.14.4.el7.x86_64 x86_64
arch_bits:64
multiplexing_api:epoll
gcc_version:4.8.5
process_id:3640
run_id:ef36ca5ae9d561d8d3d3ea979cc8481eab0da874
tcp_port:6379
uptime_in_seconds:145
uptime_in_days:0
hz:10
lru_clock:433261
executable:/usr/bin/redis-server
config_file:/etc/redis.conf

Step 6: Perform Redis Benchmarking

Run the benchmark with 15 parallel connections, for a total of 10k requests, against local redis to test its performance.

$ redis-benchmark -h 127.0.0.1 -p 6379 -n 10000 -c 15

# Sample output
................................................
====== LRANGE_600 (first 600 elements) ======
  10000 requests completed in 0.15 seconds
  15 parallel clients
  3 bytes payload
  keep alive: 1

100.00% <= 0 milliseconds
67114.09 requests per second

====== MSET (10 keys) ======
  10000 requests completed in 0.15 seconds
  15 parallel clients
  3 bytes payload
  keep alive: 1

100.00% <= 0 milliseconds
66666.66 requests per second

For more options and examples, use:

$ redis-benchmark --help

You have successfully installed Redis on CentOS 7. Our next guide will be on cluster installation of Redis on CentOS 7.