 <p>SNMP has quite a significant CPU hit on the devices in question compared to telnet; I'd recommend telnet wherever possible. (As stated in a previous answer, the IOS XR XML API would be nice, but as far as I know IOS XR is only deployed on high-end carrier grade routers).</p> <p>In terms of existing configuration management systems, two commercial players are HP Opsware, and EMC Voyence. Both will probably do what you need. I'm not aware of many open source solutions that actually support deploying changes. (<a href="http://www.shrubbery.net/rancid/" rel="nofollow noreferrer">RANCID</a>, for example, only does configuration monitoring, not pre-staging and deploying config changes).</p> <p>If you are going to roll your own solution, one thing I would recommend is sitting down with your network admin and coming up with a best-practice deployment model for the service he's providing (e.g. standardised ACL, QoS queue, and VLAN names; similar entries in ACLs that have the same function for different customers, etc.). Ensure that all the existing deployed config complies with this BP before you start your design, it will make the problem much more manageable. Best of luck.</p>