Hi guys,

I've googled this many times and nobody seems to have a clear answer.
Here is what im trying to do:
I want to add a static route to the route table on my CentOS box. I know I can do this with the following command:
route add -net 192.168.2.0 netmask 255.255.255.0 gw 192.168.120.1 dev eth0

As you know, when you reboot, static routes disappear. So what I did was write a shellscript so that every hour the shell script is run using crond.

The script i put in the following dir:
/usr/bin

The script is run as:
root

The script looks like this:
#!/bin/sh
route add -net 192.168.2.0 netmask 255.255.255.0 gw 192.168.120.1 dev eth0

permissions look like this:
-rwxrwx--- 1 root root 87 Jun 2 17:01 tunroutetest.sh

When I run this script manually from the webmin scheduled cronjobs GUI, it adds the route successfully. So I know its not my script command. However, when it is run automatically, i get the following error via email alert:

/usr/bin/tunroutetest.sh: line 2: route: command not found

How do I fix this? Why is it not finding the route command and adding it automatically via crond? Please help!

When writing scripts assume that you will not have a valid path setting.

so instead of just putting "route" and hoping for the best put "/sbin/route"

Ok, I modified it to:
#!/bin/sh
/sbin/route add -net 192.168.2.0 netmask 255.255.255.0 gw 192.168.120.1 dev eth0

and its working. Thanks! Why include /sbin when the file is actually in /usr/bin? Thanks again for your help!

By the way, I get this error in email alert:

/usr/bin/tunroutetest.sh
SIOCADDRT: File exists

Because it's the path to route not your script, your script is in /usr/bin and route is in /sbin

You'll get this error when your script runs and the route is still up.

You can either ignore the error or modify your script to check for the route first and then only try and create it if it's not already there.

Makes sense. Thank you! I modified my script with following to del route first and then add it because I dont know how to write a script to check route first (route -n) and only create it if its not already there. If you can point me in the right direction, that would be great! Thanks again for your help!

#!/bin/sh
/sbin/route del -net 192.168.2.0 netmask 255.255.255.0 gw 192.168.120.1 dev eth0
/sbin/route add -net 192.168.2.0 netmask 255.255.255.0 gw 192.168.120.1 dev eth0

Checking the existence of a route gets a little messy, you are going to need to print the route to a variable, search the output for the address your looking for, tie that into an if statement to conditionally modify the existing route. However to just get rid of the error is simple, just add " 2>/dev/null". If it is still persistent then try "2>&1>/dev/null"

/sbin/route del -net 192.168.2.0 netmask 255.255.255.0 gw 192.168.120.1 dev eth0 2>/dev/null
/sbin/route add -net 192.168.2.0 netmask 255.255.255.0 gw 192.168.120.1 dev eth0 2>/dev/null