If the IPsec tunnel is not UP, check that the ISAKMP policies match with the remote peers. This ISAKMP policy is applicable to both the Site-to-Site (L2L) and Remote Access IPsec VPN.
If the Cisco VPN Clients or the Site-to-Site VPN are not able establish the tunnel with the remote-end device, check that the two peers contain the same encryption, hash, authentication, and Diffie-Hellman parameter values and when the remote peer policy specifies a lifetime less than or equal to the lifetime in the policy that the initiator sent. If the lifetimes are not identical, the security appliance uses the shorter lifetime. If no acceptable match exists, ISAKMP refuses negotiation, and the SA is not established.
"removing peer from peer table failed - no match"This message usually appears due to mismatched ISAKMP policies or a missing NAT 0 statement.
If the Cisco VPN Client is unable to connect the head-end device, the problem can be the mismatch of ISAKMP Policy. The head-end device must match with one of the IKE Proposals of the Cisco VPN Client.
Note: For the ISAKMP policy and IPsec Transform-set that is used on the PIX/ASA, the Cisco VPN client cannot use a policy with a combination of DES and SHA. If you use DES, you need to use MD5 for the hash algorithm, or you can use the other combinations, 3DES with SHA and 3DES with MD5.
Table of ContentsIntroductionVersion HistoryPossible Future
UpdatesDocuments PurposeNAT Operation in ASA 8.3+ SectionsRule Types
Network Object NATTwice NAT / Manual NATRule Types used per SectionNAT
Types used with Twice NAT / Manual NAT and Network Obje...
Table of Contents Introduction:This document describes details on how
NAT-T works. Background: ESP encrypts all critical information,
encapsulating the entire inner TCP/UDP datagram within an ESP header.
ESP is an IP protocol in the same sense that TCP an...