The reason for the failure. Possible reasons include: 1 = other 2 = peer delete request was received 3 = contact with peer was lost 4 = local failure occurred 5 = authentication failure 6 = hash validation failure 7 = encryption failure 8 = internal error occurred 9 = system capacity failure 10 = proposal failure 11 = peer's certificate is unavailable 12 = peer's certificate was found invalid 13 = local certificate expired 14 = certificate revoke list (crl) failure 15 = peer encoding error 16 = Reference to a non-existent control tunnel 17 = Extended User authentication failed 18 = operator requested termination. 19 = An attempt to establish a tunnel was aborted by the admission control policy (this could include a simple policy that limits the maximum active tunnels) 20 = A protocol specific reason (look in the protocol-specific MIB for more info).