More 3ware and Nagios
I've extended the check_3ware.sh script a bit more.
Now the script returns OK if all your units are okay, WARNING when a unit is rebuilding, CRITICAL when an array has failed and UNKNOWN when tw_cli returns something I didn't catch. I don't know all states tw_cli can return so right now the solution is to return unknown. I'll probably extend it in the future.
You can still look at the script here.
Check 3ware controllers using Nagios
When implementing Nagios to monitor my servers I also wanted to check the RAID arrays. Our servers have 3ware controllers so I searched for a script that would do this for me. I found some perl scripts but somehow they just didn't do the trick.
Luckily 3ware provides a (closed source) admin tool called tw_cli. So, I decided to write my own check_3ware.sh script using the tw_cli tool. It's a very dumb script which outputs CRITICAL whenever one of your arrays does not return OK as state. You can get it here