Windows out of control! 16824

With a kernel update, if you don't reboot, you simply don't get the new kernel. So, you need to reboot for the update to actually be useful, but no harm is done.

A more serious situation is library updates, as newly launched programs will get the updated library, but programs that are already running will continue to use the old one. Consider any server that is implemented as multiple processes, such as many mail servers--bad things could happen during an update if you don't restart all the processes using the library.

Unfortunately, most package management systems don't seem to have a mechanism for doing that. So, unless you understand exactly what an update updated on a Linux systems, and the ramifications of it, it is a good idea to reboot if it might have updated anything used by a daemon or other running program.

Actually, for a server, you should reboot after any update, even if it is completely safe, just to make sure that you *can* still boot. If something got messed up in the update that will make your server fail to start normally, you want to find out right away, rather than find it out weeks or months later when the system goes down at 3AM due to hardware failure or something like that, and won't come back up after you fix it.

A lot of people seem to throw sound server management practices out the window in order to try to get uptime privates waving rights.

-- --Tim Smith