I have a Cisco ASA 5520 firewall device, we have configured about 60 site-to-site vpn tunnels to our clients. In the recent days at least once in a day all my VPN tunnels flaps, all I will do is "clear crypto isakmp sa" & then the VPN tunnel works fine, this has become now a regular practice, All I wanted to know the root cause for this that why this is happening only on a particular time.
I have 2 Cisco ASA with the same hardware & s/w other acting as a standby device.
Cisco Adaptive Security Appliance Software Version 8.0(2)
We have configured the outside and inside Interface with official ipv6 adresses, set a default route on outside Interface to our router, we also have definied a rule , which also gets hits, to permit tcp from inside Interface to any6.
In Syslog I also se...