UNIX for Dummies Questions & Answers

I know that schedulers handle callign scripts on different machines. If I want to call a script that's on the target machine and know whether the script ran fine or not, can it be done in shell script?

what kind of commands would that have?

Thank you

Bryan,

How does one run a script remotely on another server?

You can run a scheduler like Tivoli Workload Scheduler, sysADMIRAL, or control-m.

You can always run a cron job as you know.

However, these are not really great for on demand. However, SSH is.

This is really a multi step process. You need to setup SSH correctly and create a key pair and passphrase. Then you need to load your keys into the SSH agent so that you don't get prompted for a passphrase. The SSH agent will handle passing your passphrase to the other systems.

Example:

#ssh-add
Adding identity: /home/tester/.ssh2/id_dsa_1024_defender.pub
Need passphrase for /home/tester/.ssh2/id_dsa_1024_defender.pub
(1024-bit dsa, tester@defender, Sun Apr 30 2000 21:39:13).
Enter passphrase:

#ssh server date
Wed May 10 14:06:57 EDT 2006
#

#Now that you have SSH setup. You can take any script and scp the script to the remote server.



Sample script below
###############################################
#!/bin/sh

LOG="/tmp/MYTEST.log
##################
function if_error
##################
{
if [[ $? -ne 0 ]]; then # check return code passed to function
print "$1 TIME:$TIME" | tee -a $LOG # if rc > 0 then print error msg and quit
exit $?
fi
}

chown root:root /etc/passwd
if_error "Failed chowning /etc/passwd to root:root"

chmod 700 /etc/passwd
if_error "Failed chmoding /etc/passwd to 700"

rm -rf /etc/somedir
if_error "Failed deleting /etc/somedir"
################################################

#Okay..So SSH is working and you got a little test script with the proper error checking in it. Also, I used the tee command to redirect the output of the script to the screen and to a log file in tmp.

scp $USER@$HOST:$PATH/$SCRIPT $USER@$HOST:/tmp/$SCRIPT
ssh -l $USER $HOST chmod 700 /tmp/$SCRIPT
ssh -l $USER $HOST /tmp/$SCRIPT
ssh -l $USER HOST rm /tmp/$SCRIPT

1. Copied script to server
2. Changed permissions
3. Executed script that will write to log file and screen cause I wrote it like that.
4. rm the script


Hope this is helpful.

-X