Is there a Linux/Unix based operating system used for training sysadmins?
Some bugs would be deliberately included in the system and the training candidate is supposed to solve all of them. It should be something similar to WebGoat.
Unix & Linux Stack Exchange is a question and answer site for users of Linux, FreeBSD and other Un*x-like operating systems. It only takes a minute to sign up.Sign up to join this community
To my knowledge, there is not a specific distro for this, but you might want to look at http://trouble-maker.sourceforge.net/ and make use of it on your favorite distro.
there is a college professor that put together a good tutorial site called linuxzoo.net with assorted tutorials that will familiarize you with Unix/Linux basics, all the way up to beginning/intermediate administration topics...it's a great safe environment to start in where you don't have to worry about breaking anything.
Creating an account is free and its usage is also free.
I'm afraid this isn't much help to you; I'm including it here for its curio value only. It seems there was such a distro started by a German security lecturer who wanted to teach his students about vulnerabilities. I came across it by accident:
Distrowatch (link above) says it's been discontinued, though and its website seems dead.