Currently we have a client that has a ASA 5505 at a co-location and a PIX firewall in their office with a site-to-site VPN tunnel established between them. They are looking to put in a UC500 in their office.
What needs to be done on the UC500 to re-establish the VPN tunnel? Is it simply a matter of copying the config from the PIX device and copying it into the UC500 configs?
Of course this will work... I do it all the time... that just is some extra access-list commands to allow the VPN client to talk to both subnets.
Keep in mind the UC500 doesn't have to replace the PIX (unless you want to). THe PIX and the UC500 can work together...
The UC500 will only support a minimal amount of IPSEC tunnels and the PIX will out perform it in that way...
I assume you'll be removing the PIX and using the IOS FW features of the UC520 and establishing the VPN from the UC520 to the ASA5505? A good source of reference in setting up site-to-site VPN can be found here within the "SBCS-MultiSite-appnote"; step 6 page 9. It also includes references to other documentation you will find useful in this process. Review this material and see if this give's you the details you're looking for.