The WebReboot Plugin for Nagios is a suite of commands that can be used within Nagios to monitor a server and take corrective action if necessary via the WebReboot line of products. For example, the plugin can be used to alert you if a host is powered down, versus simply not responding to network requests. Likewise, it can be used to reboot a server if a host fails to respond to ping, or to shut down a server when a critical temperature threshold is exceeded. The commands can be mixed-and-matched with all existing Nagios commands, maximizing total network coverage.
memtester is a user-space utility for testing the memory subsystem in a computer to determine if it is faulty. It does a good job of finding intermittent faults and non-deterministic faults. It has many tests to help catch borderline memory. memtester should compile and run on any 32- or 64-bit Unix or Unix-like system.
NASLite is a Network Attached Storage (NAS) server operating system designed to transform a basic computer into a dedicated file server. Utilizing highly optimized versions of Samba, uCLibc, BusyBox, and various other Linux tools, it provides SMB/CIFS, FTP, or NFS filesystem support. It accommodates multiple client OSes: Windows, Mac OS X, and Linux. NASLite offers SMART disk monitoring and large file support, and is incredibly easy to install and administer.