These are the troubleshooting methodologies :
Be aware of any changes to an active Cisco Easy VPN Remote configuration or IP address changes to the involved interfaces.
Enable debugging of the Cisco Easy VPN Remote feature using the debug crypto ipsec client ezvpn command.
Enable debugging of IKE events using the debug crypto ipsec and debug crypto isakmp commands.
Display the active IPsec VPN connections using the show crypto engine connections active command.
To reset the VPN connection, use the clear crypto ipsec client ezvpn command.
http://www.cisco.com/en/US/tech/tk583/tk372/technologies_configuration_example09186a0080808395.shtml
http://www.cisco.com/en/US/docs/ios/12_2t/12_2t8/feature/guide/ftunity.html#wp1192045
