RANCID, the Really Awesome New Cisco confIg Differ

Rancid maintains CVS controlled copies of router (device) configurations.
I uses expect to login to a list of devices and collect their software
configuration, hardware information, etc.  The collected data is formatted,
trimmed, etc.  Each is diff(1)'d against the previous and the output is
e-mailed to a mail list, then committed to the cvs repository.

It supports various Cisco routers & switches, Juniper Networks routers, and
several others.

Besides being useful for tracking configuration changes, Rancid comes with
several scripts that are generally useful for network management, including
the expect scripts that automate device logins.

Homepage:
https://www.shrubbery.net/rancid/
