Power loss at company

Solution 1:

Before the outage:

• Power everything off - workstations, servers, printers, switches, the works.
• Turn off your UPS' so they don't panic when power is lost.

After outage in this order:

• Turn on UPS
• Turn on networking (router, switches etc)
• Turn on servers
• Turn on workstations
• Turn on everything else

Have a test plan ready so you can test important functionality is working

• Internet connectivity
• Email, printing etc

If possible, have a laptop with a separate network connection handy (ie: you can get to the internet without your work router working). That way you have a way to ask for help here if something goes wrong with the networking when it comes back up. :)

You should be fine though - the fact that you took the time to ask here shows you already have the requisite "clue" required for IT support!

Solution 2:

Having just done through a datacenter shutdown in the last week, this is fresh on my mind ;). Yes, shutting everything down needs to be done. Some things can tolerate having the power yanked out from underneath them, and they typically can be identified by not having a power switch on them. Depending on what the heck the facilities people are doing, you may want to physically unplug higher value assets from the wall.

Sometimes you can get sizeable power-surges when power returns, and that can kill gear. Also, be aware of your start-up load. EVERYTHING powering on at once may be enough to pop breakers and bring everything down again. That sucks. Try for a staged power-on to get around this.

EDIT: We had a case where the transfer switch for the generator didn't fire, and the UPS ran out of batteries. When utility came back, everything powered on at once. 20 seconds later the UPS hit Overload and dropped load from the room again. By then enough techs had arrived on site (it HAD to happen during a weekend) that they managed to get enough stuff turned off at the rack-switches that when utility came back again the room didn't drop again. That yo-yo cost us a lot of hardware, and it was week recovering from some of the damage.

Solution 3:

The only thing I'd add is to make sure you have all your support contracts and replacement parts easily findable. I'm sure you do, but double and triple check that. If you've had servers that haven't powered down in a long time you'll occasionally find issues with all the moving parts (hard drive bearings/motors, fan motors and bearings and some really silly stuff that we normally don't think about).
If you can be there for the duration, make up a list for your important servers including their service tag, configurations, where the backups are and any people that might be responsible for apps on each machine. Tape that up on the side of the server in question, or have it in a binder in the datacenter for when you start trying to bring things back up. You don't want to have to keep running all over your office if something is broken.