Fri, 26 Aug 2005
rng-tools
Many modern computers come with hardware random number generators that are
supported by newer Linux kernels. They generally are available via a file in
/dev, have varying speeds, and are occasionally buggy. However, when they
work properly they can help out servers quite a bit by providing a steady
source of entropy that would otherwise be lacking. If you’ve ever tried to
generate a gpg key on a remote server and have it hang on you, you’ve run out
of entropy.
rng-tools is a collection of tools that help make it easy to use the
hardware random number generator safely. At the core of the toolkit is rngd,
a daemon which reads from the hardware random device, tests the bits read for
randomness, and then feeds them into the kernel’s normal entropy pool via
/dev/random. Like all great utilities, it’s pretty much fire and forget;
once installed, it will figure out if you have a useable hardware random device
and start to use it or it will exit with a log message telling you that you are
out of luck.