I had another Solaris 9 learning experience today: I came in to find my ssh sessions to my Ultra 10 test machine dead, because the machine was powered off. This was more than a little bit disconcerting, since the last thing I had left it doing was installing the current Solaris 9 patch set. (It took sufficiently long that I'd had to go home before it finished.)

Powering the machine on showed not a normal boot sequence, but a message about restoring the system. This caused me to remember that when I had installed the system, I'd said yes to an offer to have 'power management' software installed. (Unfortunately the installer does not have very many clear explanations of what the software packages all do.)

In the PC world I usually operate in, 'power management' is things like spinning down disks and dropping into low-power CPU states when the machine is idle. In the SPARC world, it turns out that 'power management' is turning the machine off entirely.

Fortunately I was able to find the dtpower program after some quick Googling. Unfortunately dtpower doesn't run over a ssh X connection for some reason, so I had to fire up dtlogin, log in, and run it to shut this feature off. (There is probably a way to fire up the X server and the environment from a console login, but starting dtlogin was faster than trying to figure it out.)

(This whole episode is my fault, not Solaris 9's. I should have read the documentation before firing up the installer, and certainly before answering installer questions I didn't fully understand. But at least I've stubbed my toe on this now, in case I ever have to deal with Sparcs that mysteriously power themselves off every so often.)