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Problem with the CRYPTO-4-PKT_REPLAY_ERR replay check failed message


In dynamips I created a GRE tunnel over a VPN between 2 routers over a simulated Internet connection and it works great. I'm able to create EIGRP neighborships, exchange routes and ping across it all day without losing a ping.

Next, I created a l2TPv3 tunnel across the VPN to have a VLAN existing on both sides. Shortly after sending traffic across the l2TPv3 tunnel, the EIGRP neighborship fails, the tunnel breakes, and I start losing pings. The tunnel will then re-establish and the fail again and again and my pings will fail and succeed for a bit then fail.

Console message:

%CRYPTO-4-PKT_REPLAY_ERR replay check failed

From looking around for work-arounds I've increased the crypto ipsec security-association replay window-size to 1028 and used encryption only on both sides of the VPN but, still the tunnel breaks.

See attached diagram.

Any suggestions?

Thank you, Pat.

Everyone's tags (2)
New Member

Problem with the CRYPTO-4-PKT_REPLAY_ERR replay check failed mes

Sorry for off-post reply, Patrick did you previously work at Dell? Looking for former Dell employee who did some design work for me last fall and have a question.

Thank you,


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