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L2TP between Cisco and Juniper

Hi, on a Juniper backbone, we have a Cisco AS5400 acts as a LAC, while there's Juniper device act as a LNS. I've few problems that I bumped into and dunno what is the cause. Let me summarize it into point form:

i. I've made the L2TP tunnel able to establish, but as far as I concern, LAC is tranparent, which means it only need to have a single default route to the LNS. And if a remote-site establish a connection through ISDN to the LAC, the authentication is done by the LNS itself. Hence the connection is directly to the LNS, LAC just act as a medium to transfer the connection aint it? But when the L2TP tunnel establish, the remote end get assigned an IP by the LNS, in this case, while at the LNS side the loopback is, I can't even ping to, but i still get the IP assigned.

ii. When I did some "debug ip packet", in the mean time if I ping to, the message appeared saying "encap failed". While if i ping to (failed), i can't see anything flow out although "debug ip packet" is on.

are you guys having any idea, please see through the text file, I've included the configuration and some captures. Appreciate if you guys could shed some lights to my problems.

Thanks a million


Re: L2TP between Cisco and Juniper

When you get an IP from the LNS are you able to ping the IP from the Remote end router. Also what is the IP ? Why is the default route pointing to that ?

Can you try the static route

ip route Serial1/1:15 and see if it helps

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