Ali cloud server CentOS installation redis

What is Redis?

English official website: https://redis.io/
Chinese document: http://redis.p2hp.com/

The open source, in-memory data store used by millions of developers as a database, cache, streaming engine, and message broker. The open source, in-memory data store used by millions of developers as a database, cache
, streaming engine, and message broker.

Install Redis on CentOS 7

Using yum install redis directly on the terminal will prompt that there are no packages available.

Redis packages are not included in the default CentOS repositories. We will install Redis version 5.0.2 from the Remi repository.

Installation is very easy, just follow these steps:

1. First enable the Remi repository by running the following command in an SSH terminal:

   sudo yum install epel-release yum-utils
   sudo yum install http://rpms.remirepo.net/enterprise/remi-release-7.rpmsudo 
   yum-config-manager --enable remi
   

2. Install the Redis package by typing:

   sudo yum install redis
   

3. After the installation is complete, start the Redis service and enable the following command to enable it to start automatically at boot time:

systemctl start redis
systemctl enable redis

Created symlink /etc/systemd/system/multi-user.target.wants/redis.service → /usr/lib/systemd/system/redis.service.

To check the status of the service, enter the following command:

systemctl status redis

You should see something similar to:

● 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 Mon 2021-01-04 11:38:43 CST; 3min 54s ago
 Main PID: 81547 (redis-server)
    Tasks: 4 (limit: 11498)
   Memory: 6.6M
   CGroup: /system.slice/redis.service
           └─81547 /usr/bin/redis-server 127.0.0.1:6379

1月 04 11:38:43 wywar systemd[1]: Starting Redis persistent key-value database...
1月 04 11:38:43 wywar systemd[1]: Started Redis persistent key-value database.

If IPv6 is disabled on your server, the Redis service will fail to start.

Congratulations, at this point you have Redis installed and running on your CentOS 7 server.

Configure Redis remote access

By default, Redis does not allow remote connections. You can only connect to the Redis server from the computer running Redis at 127.0.0.1 (localhost).

Follow the steps below only if you want to connect to the Redis server from a remote host.

If using a single server setup, and the application and Redis are running on the same machine, remote access should not be enabled.

To configure Redis to accept remote connections, open the Redis configuration file with a text editor:

sudo nano /etc/redis.conf

Find the line that starts with , bind 127.0.0.1and add your server's private IP address after it 127.0.0.1.

/etc/redis.conf

# IF YOU ARE SURE YOU WANT YOUR INSTANCE TO LISTEN TO ALL THE INTERFACES
# JUST COMMENT THE FOLLOWING LINE.
# ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
bind 127.0.0.1 192.168.121.233

Make sure 192.168.121.233to replace with your IP address. Save the file and close the editor.

Restart the Redis service for the changes to take effect:

sudo systemctl restart redis
# service redis restart

Use the following sscommand to verify that the Redis server is listening on the port on the private interface 6379:

ss -an | grep 6379

You should see something similar to the following:

tcp    LISTEN     0      128    192.168.121.233:6379            *:*
tcp    LISTEN     0      128    127.0.0.1:6379                  *:*

Next, you need to add firewall rules to enable traffic from the remote computer on the TCP port 6379.

Assuming you are using FirewallDa firewall to manage the firewall and you want to allow 192.168.121.0/24access from a subnet, you can run the following command:

sudo firewall-cmd --new-zone=redis --permanentsudo firewall-cmd --zone=redis --add-port=6379/tcp --permanentsudo firewall-cmd --zone=redis --add-source=192.168.121.0/24 --permanentsudo firewall-cmd --reload

The above command creates a new zone named redis, opens ports 6379and allows access from the private network.

At this point, the Redis server will accept remote connections on TCP port 6379.

Make sure to configure your firewall to only accept connections from trusted IP ranges.

To verify that everything is set up correctly, you can try to redis-cliping the Redis server to the remote machine using the utility, which provides a command line interface to the Redis server:

redis-cli -h <REDIS_IP_ADDRESS> ping

The command should return the following response PONG:

PONG

in conclusion

Congratulations, you have successfully installed Redis on your CentOS 7 server. To learn more about how to use Redis, visit its official documentation page.