I've got two 2600 routers connected to each other using site-to-site vpn. Problem is the connection goes down after a while. When I first start the routers the connection is there, but I come back half an hour later and there's no tunnel, neither router can see the other, it all has the feeling of being flakey and unreliable. In the vpn setup I included the command:
router#crypto ipsec security-association lifetime seconds 86400
on both machines but still the connection goes down.
I also put in:
router#crypto ipsec df-bit clear
but the connection still goes down.
If there's another command I'm missing that helps keeps the connection stable I'd be grateful to know it. Thanks for any help.