developerWorks: Administer Linux on the Fly

“Anyone who has administered a system of commercial importance
knows the value of uptime–or, conversely, knows the headaches you
get from users because of downtime. One of the main reasons a
company will run a UNIX server is because of its reliability and
stability. If managed carefully, there’s usually no need to restart
these servers for long periods of time. And to improve matters
further, there are administrative tasks–even at the kernel
level–that you can perform on the fly, keeping your servers
available. While you may still need to restart a system to upgrade
hardware or if someone trips over the power cord, it’s good to know
that many administrative tasks can be performed without disrupting
service.

“This article includes hints and tips for performing various
administrative tasks and changing your system without rebooting.
Linux provides various ways to change underlying operating system
values and settings while keeping the system up and running. These
come in two basic forms, those that are general to all Linux
systems and are provided in the Linux kernel (you can find more
information about the Linux kernel and download kernel source at
the Linux Kernel Archives), and those that are distribution
specific and provided by the vendor. This article deals with both
types…”

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