Automation tip — adjust a file on a lot of servers

I have a customer that has 40 servers that perform a given function. They are comprised of physical machines and Solaris zones. I needed to adjust a file on each of those machines. I was not about to ssh into each machine and then start up vi and adjust the file by hand.

Here is what I did instead

for host in 1 2 3 4 5; do
  for zone in 1 2 3 4 5 6 7 8; do
    ssh -q $host\-$zone 'perl -p -i -e "s/ReplaceMe/WithMe/g" /path/to/file'
  done
done

I’m confident that I’m not the first person do this but I thought it was creative all the same. Combines a PERL one liner with two nested for loops for nice system automation.

See my post on consistency, this is a great example of why it is necessary.