What is the difference in the shutdown (and possibly startup) between a power loss and a controlled shutdown (such as a reboot or literal shutdown) in Linux, and in particular, Ubuntu server 10.04 LTS?
Most important to me: the differences in how networking is handled in these two situations.
This article explains some of the problems when a system is not gracefully shut down - http://www.halfgaar.net/why-power-failures-are-bad-for-your-data. With a linux server, acpid helps shut down the system gracefully when the power button is pressed.
When you shutdown and/or reboot a server the services are gracefully stopped, any un-written pages in memory are written to disk where they belong, etc.
When the power goes out, poof everything is just gone. Any data that existed only in memory is lost.