VPN client unable to establish MS SMS 2.0 remote control session

[b.bernius]

I am able to establish a VPN connection through a 3000 Concentrator that is owned and supported by our local ISP. When I run MS Systems Management Server 2.0 SP2 from the VPN client I am able to connect to the SMS site server but when I try to expand the Collections Group to select a system to remote control I get an error that RPC Server service is unavailable. I have discussed this with the ISP and their stance is that IP connectivity has been established, no ports are being blocked therefor SMS TCP and UDP ports being blocked is not the issue, and that the issue could be because addresses are getting natted. I use a cable connection to connect to the VPN with a IP address supplied by the cable provider. Any suggestions on how to enable remote control through VPN.

[s.jankowski]

There are only two instances that I know of when the assigned IP is changed/transformed: 1) When a firewall deployed enroute is performing natting or 2) Your concentrator is configured for IKE Mode Configuration. If indeed your provider is correct and the problem is due to transformed addresses, you need to check if there is a firewall deployed somewhere in the route that your packets are taking. Further, you need to confirm if IKE Mode configuration is configured and that if configured, what is the address being pushed to you.