CentOS 6.9 Redis Installation and basic configuration (i)

Use the following command to update the Yum source and install the Redis service:

RPM-UVH http://mirrors.kernel.org/fedora-epel/6/i386/epel-release-6-8.noarch.rpm

Yuminstall-y Redis

Serviceredis start

Chkconfigredis on

After the installation, we found a strange problem (not sure if it is related to the Redis version, CentOS 7.4 did not encounter a similar problem):

We view the Redis service status:

But we're looking at the Redis service port listening Condition:

You can see that the Redis service is listening normally and can be connected locally using REDIS-CLI:

Understanding that Serviceredis status is actually going to invoke the status method of/etc/init.d/redis This script file, let's take a look at/etc/init.d/redis this file content (irrelevant part we use ...). Omitted):

#!/bin/sh ...... Name= "Redis-server" exec= "/usr/bin/$name" shut= "/usr/libexec/redis-shutdown" Pidfile= "/var/run/redis_6379.pid" Redis_config= "/etc/redis.conf" ...... Start () { [f $REDIS _config] | | Exit 6 [x $exec] | | Exit 5 Echo-n $ "Starting $name:" Daemon--user ${redis_user-redis} "$exec $REDIS _config--daemonize yes--pidfile $pidfile" Retval=$? Echo [$retval-eq 0] && Touch $lockfile Return $retval } ...... Rh_status () { Status-p $pidfile $name } Rh_status_q () { Rh_status >/dev/null 2>&1 } Case "$" in Start Rh_status_q && Exit 0 $ ;; Stop Rh_status_q | | Exit 0 $ ;; Restart) $ ;; Reload Rh_status_q | | Exit 7 $ ;; Force-reload) Force_reload ;; Status Rh_status ;; Condrestart|try-restart) Rh_status_q | | Exit 0 Restart ;; *) echo $ "Usage: $ {Start|stop|status|restart|condrestart|try-restart}" Exit 2 Esac Exit $?

We see that the Rh_status method is invoked when the Redisstatus parameter is invoked, which actually checks the PID file. Let's take a look at the start method, you will call/usr/bin/redis-server this execution file, corresponding to generate a PID file, see a daemonize parameter, to Redis configuration file to view this parameter and the PID file path:

You can see that the default Redis is run in daemon, but the path to the PID file in the configuration file is inconsistent with the path in the/etc/init.d/redis script file, so we try to modify the PID file path in the script: pidfile= "/var/run/ Redis.pid "

Try restarting the service again discovery still does not work, see/var/run There is no redis PID file generated below:

It's strange that Redis does not have permission to create a directory. Let's create a/var/run/redis directory by hand and assign a permission to the Redis User:

Try restarting the service again, this is normal: