Once upon a time, it was conventional Unix server wisdom to reboot every month or so to make sure it was working correctly. These days many Linux system administrators boast about the number of days their servers have been up and running without interruption. BSD and other Unix-like OS users also claim similar uptimes, sometimes as long as or even longer than a year without rebooting. One might ask: is this actually a good practice?
Linux is known for its efficiency, and it can run for several days, months, even years without losing its integrity or needing to refresh itself. Therefore, rebooting is not usually necessary and would only result in downtime, which would be especially troubling if you are serving websites to the public.
One exception to the rule occurs when you need to perform a major security update to the kernel. In such a case, a reboot will be necessary to boot the new kernel. For most updates, even security updates, however, a reboot is not required, which may differ considerably from Windows servers.
Aside from security updates, your server should only be rebooted if it hangs completely. Most other problems can be fixed without resorting to a reboot.