network administrator users on Firewall ASA we need to track what command modified and who add them from our administrator

Hi kindly i need help how to take secure daily automatic back up from cisco ASA and Router and Sws through SCP  i hope to have also a software  recommendation software and best way to achieve this request 

kindly i need to ask about the below senario i need to configure a vpn site to site over adsl between two sitesthe problem is only with the site which have a cisco router model 881this cisco router 878 have only 4 swithport and no external interfaces...