Viper is a system for completely automated installation and configuration of Debian GNU/Linux-based systems. It uses a modern approach with debian-installer and puppet, works with existing Debian packages, and does not require any custom patching of either install media, client, or server. The basis of the whole system is an LDAP server containing all configuration data.
Chev is a sane by default vulnerability check script that checks NIST and US Cert RSS feeds for a short list of software that you configure. It has two levels of priority, warn and critical, which allows for easy use with Nagios as a stand-alone script or in a cron job. Just add strings for your major pieces of software and chev will tell you when a vulnerability has been released.
The Marionette Collective (mcollective) is a framework to build server orchestration or parallel job execution systems. It uses modern technologies and concepts that make it ideal for large and cloud-based infrastructures. It's specifically geared towards systems administration tasks, but can be seen as a generic framework too.
The Logfile Navigator, lnav for short, is a curses-based tool for viewing and analyzing log files. The value added by lnav over text viewers or editors is that it takes advantage of any semantic information that can be gleaned from the log file, such as timestamps and log levels. Using this extra semantic information, lnav can do things like interleaving messages from different files, generate histograms of messages over time, and provide hotkeys for navigating through the file. These features are meant to allow the user to quickly and efficiently focus on problems.
GoAccess is a real-time Web log analyzer and interactive viewer for almost every Web server. It runs in a terminal and provides fast and valuable HTTP statistics for system administrators that require log monitoring and visual reports on the fly. GoAccess can monitor unique visitors, browsers, spiders, OS, hosts and IP geolocation, keyphrases, referring sites, status codes, etc. It has support for IPv6 and it parses nearly any Web log format.
x509watch is a simple command line application that can be used to list soon expiring or already expired X.509 certificates, such as SSL certificates. All certificates are searched by default in the standard PKI directory, but any other directory can be specified as a parameter. Only Base64 encoded DER and PEM X.509 certificates are supported.
HATop is an interactive ncurses client and real-time monitoring and statistics displaying tool for the HAProxy TCP/HTTP load balancer. HATop's appearance is similar to top(1). It supports various modes for detailed statistics of all configured proxies and services in near real-time. In addition, it features an interactive CLI for the HAProxy Unix socket. This allows administrators to control the given HAProxy instance (change server weight, put servers into maintenance mode, etc.) directly out of HATop (using keybinds or the CLI) and monitor the results immediately.