Shell scripting- how do I do this?

Bes · 23 May 2007 at 09:55

Hi

I want to write a script that SSH'es to a number of boxes
(i.e. for i in box1 box2 box3

do
..)

and so on, the script works perfectly unless one of the boxes is unavailable, in which case it grinds to a halt. Is there any way around this?

Thanks

JIMA · 23 May 2007 at 22:56

Hi,

Have you tried executing each ssh as a background process?

Failing that, maybe a small Perl script that forks a new process for each ssh call would be an option?

Hope that helps.
Jim

Shoseki · 24 May 2007 at 00:28

hmm, I seem to remember a multi-ssh client that works by opening a seperate shell for each, and so they operate independantly, and executables can be each called seperately with the same variables etc. Can't remember what it was called, but google is your friend :S

matja · 24 May 2007 at 09:42

grinds to a halt how? ssh waiting to connect? try -o ConnectTimeout=10 (seconds)

Anthony · 24 May 2007 at 15:49

If the server is down, something like this in your script should be ok to begin with ...

ping -c 2 $i 1>/dev/null 2>&1
if [[ $? -eq 0 ]]
then
ssh ....
fi

Add an else statement if you want to be told that the remote host isn't responding. (eg; mail or snmp trap) You could also do something similar to check the return code from the ssh and set ConnectionAttempts in your ssh_config to something low.