Hardening Interface used for VPN

[GRANT3779]

Are there "must do's" on outside interfaces used for Site to Site VPNs? There is no NAT used on the interfaces. Looking for advice on what I should be applying to the interface in terms of ACL. At the moment,the only thing I have applied is to allow my "Interesting" traffic through the VPN. Should I be limiting incoming traffic etc...? New to VPN setup and don't want to leave the network wide open..

Any advice is appreciated.

Thanks

[Julio Carvajal]

There is no NAT used on the interfaces

It can be NAT on that interface, no issue at all.

Are there "must do's" on outside interfaces used for Site to Site VPNs?

You could allow only ISAKMP and IPSec traffic from valid trusted IP addresses and the regular checks, nothing different from the usual.

Regards