CentOS - Adding an Nginx init script


If you decided to install Nginx via source (see the previous article) you would have the latest and greatest version.

However, one disadvantage of installing from source is that init scripts are not created. No problem, let's go ahead and create one for easy control of Nginx and to ensure it restarts on a reboot.

Contents

Assumption

I am assuming you have followed the previous article and installed Nginx from source.

If you have used other options or have placed the Nginx binary in a directory other than /usr/local/sbin/ then you will need to adjust the script shown below to match your installation.

Stop

If you have Nginx running then stop the process using:

sudo kill `cat /usr/local/nginx/logs/nginx.pid`

Init script

The script I use below is from a CentOS yum install and has been adapted to take into account our custom install of Nginx.

Let's go ahead and create the script:

sudo nano /etc/init.d/nginx

Inside the blank file place the following:

#!/bin/sh
#
# nginx - this script starts and stops the nginx daemin
#
# chkconfig:   - 85 15 
# description:  Nginx is an HTTP(S) server, HTTP(S) reverse \
#               proxy and IMAP/POP3 proxy server
# processname: nginx
# config:      /usr/local/nginx/conf/nginx.conf
# pidfile:     /usr/local/nginx/logs/nginx.pid
 
# Source function library.
. /etc/rc.d/init.d/functions
 
# Source networking configuration.
. /etc/sysconfig/network
 
# Check that networking is up.
[ "$NETWORKING" = "no" ] && exit 0
 
nginx="/usr/local/nginx/sbin/nginx"
prog=$(basename $nginx)
 
NGINX_CONF_FILE="/usr/local/nginx/conf/nginx.conf"
 
lockfile=/var/lock/subsys/nginx
 
start() {
    [ -x $nginx ] || exit 5
    [ -f $NGINX_CONF_FILE ] || exit 6
    echo -n $"Starting $prog: "
    daemon $nginx -c $NGINX_CONF_FILE
    retval=$?
    echo
    [ $retval -eq 0 ] && touch $lockfile
    return $retval
}
 
stop() {
    echo -n $"Stopping $prog: "
    killproc $prog -QUIT
    retval=$?
    echo
    [ $retval -eq 0 ] && rm -f $lockfile
    return $retval
}
 
restart() {
    configtest || return $?
    stop
    start
}
 
reload() {
    configtest || return $?
    echo -n $"Reloading $prog: "
    killproc $nginx -HUP
    RETVAL=$?
    echo
}
 
force_reload() {
    restart
}
 
configtest() {
  $nginx -t -c $NGINX_CONF_FILE
}
 
rh_status() {
    status $prog
}
 
rh_status_q() {
    rh_status >/dev/null 2>&1
}
 
case "$1" in
    start)
        rh_status_q && exit 0
        $1
        ;;
    stop)
        rh_status_q || exit 0
        $1
        ;;
    restart|configtest)
        $1
        ;;
    reload)
        rh_status_q || exit 7
        $1
        ;;
    force-reload)
        force_reload
        ;;
    status)
        rh_status
        ;;
    condrestart|try-restart)
        rh_status_q || exit 0
            ;;
    *)
        echo $"Usage: $0 {start|stop|status|restart|condrestart|try-restart|reload|force-reload|configtest}"
        exit 2
esac

There's not really the space to go into the workings of the script but suffice to say, it defines where the main Nginx binary and pid files are located so Nginx can be started correctly.

Execute

As the init file is a shell script, it needs to have executable permissions.

We set them like so:

sudo chmod +x /etc/init.d/nginx

Chkconfig

Now we have the base script prepared, we need to add it to the default run levels:

sudo /sbin/chkconfig nginx on

Let's check our work to confirm:

sudo /sbin/chkconfig --list nginx
nginx           0:off   1:off   2:on    3:on    4:on    5:on    6:off

Done.

The script will now be called on a reboot so Nginx will automatically start.

Start, Stop and Restart

Now we can start, stop, restart, and reload Nginx using these commands:

sudo /etc/init.d/nginx start
...
sudo /etc/init.d/nginx stop
...
sudo /etc/init.d/nginx restart
...
sudo /etc/init.d/nginx reload

You can also check the current status as well as the configuration syntax:

sudo /etc/init.d/nginx status
...
sudo /etc/init.d/nginx configtest

Summary

Adding a process to the run levels like this saves a lot of frustration and effort, not only in manually starting and stopping the process, but it having it automatically start on a reboot.


Posted by [czar]
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