Adding our own Linux startup scripts

Do we need to start something when Linux system starts?
Its not a service.... But I need to run this command when system starts....

Yes here is a small part which astonished me as I have not learnt this for years and missed it when I need....

Let us take a sample case: We might need to start a SVN daemon on the system.
#svnserve -d /srv/repositories

We need to run the above command on every start-up autiomatically. So we don't need to start this daemon manually.

Simple way is add this along with other startup scripts. Find which runlevel the system runs normally.

[root@sf03 ~]# runlevel
N 3
[root@sf03 ~]#

Our server runs in run-level 3 so lets take that as an example.
The server runs on Fedora Linux 10

The startup scripts for run-level 3 resides in the directory /etc/rc.d/rc3.d/
The scripts for run-level 5 will be at /etc/rc.d/5.d/

The directory contains shell scripts that runs on the ascending order on by one.

The last script that runs is S99local

Which has the content similar to this.
[root@sf03 ~]# cat /etc/rc.d/rc3.d/S99local
#!/bin/sh
#
# This script will be executed *after* all the other init scripts.
# You can put your own initialization stuff in here if you don't
# want to do the full Sys V style init stuff.

touch /var/lock/subsys/local
[root@sf03 ~]#

Use the vi editor and add the startup command we need to add to this.

Example:

[root@sf03 ~]# cat /etc/rc.d/rc3.d/S99local
#!/bin/sh
#
# This script will be executed *after* all the other init scripts.
# You can put your own initialization stuff in here if you don't
# want to do the full Sys V style init stuff.

touch /var/lock/subsys/local

# Start SVN Server at startup

svnserve -d /srv/repositories

[root@sf03 ~]#

Restart the server and check the script.