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VPN 3005, cannot ping with xdsl client

our remote users are connecting to our Cisco vpn concentrator through cable modems and some are using dsl modem connections all using vpn client version 3.1. The cable modem users are able to authenticate without issue to our private network, these users get their ip addresses through the cable company via dhcp but the DSL users all use an assigned static ip and after the dsl users successfully connect to the VPN server they are unable to ping local or Internet names and addresses. I've read about the problems DSL apparantly has with MTUs smaller than 1500 and breaking down those packets causing ping errors. Does this problem seem to relate to the MTU issue, or is there something else we should check? How can one correct the MTU issue? Our remote people are using both Win98se and Win2k sp2.

Cisco Employee

Re: VPN 3005, cannot ping with xdsl client

Are you doing NAT on the dsl router. Looks like you need to turn on nat transparency on both the client and concentrator for it to work. MTU issue would at least allow you to ping (as it is just a small packet) but might have issues with packet with larger sizes, which is not what you are having.

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