As sysadmins, many times the entire task laid out in front of us has no documentation. One of the biggest skill an admin can have is the ability to problem solve, breaking down a large task into smaller sub-tasks. Often times, you might be able to find documentation on some of those sub-tasks. A perfect example is upgrading a server from Solaris 9 with root in an SVM mirror to Solaris 10 with a ZFS mirror. Not only is this large task doable, but thanks to LiveUpgrade, it can be done with less than 10 minutes of downtime (3 reboots @ roughly 3 minutes each)!

Dangit, I knew I forgot something today!!! Today was the day that some very "in-the-know" Sun engineers participated in an open chat about OpenSolaris on Slashdot. For those of you like me who were too busy fighting fires to participate, here is a link to the transcript. I wish I could make it to CommuntyOne West this year, but I found out about it too late. Anyone going?

Here's how to leverage LiveUpgrade to safely upgrade from Solaris 9 to Solaris 10 using a spare disk. No data is ever deleted, and to roll back to Solaris 9, all you need is one command and a reboot.

Like most, I learned shell scripting by following examples. Well, unfortunately, most of the samples I learned from used the 'seq' binary to execute a simple for loop like so:

for i in `seq 1 10`; do
echo $i
done

I discovered why this is bad today - not all Unixes (Solaris and Darwin included) come with it. Not to mention we're forking a process where we don't need it. On bash, use the built-in brace expansion instead:

for i in {1..10}; do
echo $i
done