cucumber-puppet is the glue between cucumber and Puppet, allowing you to write behavioural tests, or features as cucumber calls it, for your Puppet manifest.

DNS Knife is a good tool to check if your DNS setup is ok, it checks the parent servers, it checks for if your nameservers are listed on the parent server, checks if all your nameservers are reachable and are authoritative. And so on and so on…

Video of Stephen Nelson-Smith speaking about Git for sysadmins - how it works, how to use it, how to support it, and how it compares to other version control systems.

A simple command-line tool to be able to grab real-time stats from memcache.

pigz, which stands for parallel implementation of gzip, is a fully functional replacement for gzip that exploits multiple processors and multiple cores to the hilt when compressing data. pigz was written by Mark Adler, and uses the zlib and pthread libraries. John Allspaw notes that “When you’ve got massive files, this can be a pretty big advantage, especially when you’ve got lots of cores sitting around.”.

Agile Testing’s Grig Gheorghiu provides a simple, step-by-step tutorial for installing Opscode Chef and getting a Chef client to talk to a Chef server.

A large crowdsourced list of sysadmin diagnostic tools available on Linux.