If you're on Linux and you want to connect to a Cisco VPN, Cisco provides an Anyconnect client for Linux, unfortunately it's not well integrated with your linux network manager.
Openconnect is a great alternative to the Anyconnect client ...
Here is a little script to retrieve and store the output of command periodically on your cisco router. It can be usefull when logs don't want to speak.
conf t
!
event manager session cli username <myusername>
event manager applet ...
Here is a little tip if you're using Sublime Text (which is a really great text editor with many useful features) It's quite easy, you just have to download the IOS language definitions and put it under your Sublime Text ...