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icmp outside interface

Below is the commands I have that allow hosts behind firewall to ping and tracert but dissallow icmp to any hosts that have static mappings from the outside. That part works, however you are still able to ping the outside interface from the outside world just fine. What do I need to add/change to stop this from happening?

access-list acl_inbound permit icmp any any echo-reply

access-list acl_inbound permit icmp any any time-exceeded

access-list acl_inbound permit icmp any any timestamp-request

access-list acl_inbound permit icmp any any timestamp-reply

access-list acl_inbound permit icmp any any information-request

access-list acl_inbound permit icmp any any information-reply

access-group acl_inbound in interface outside

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Re: icmp outside interface

ACLs do not affect traffic destined to or from the Pix as a host. To prevent this from happening, use the [icmp] command to disable or tune your Pix's ICMP behavior. This is done per-interface.

icmp deny any outside

If you do VPNs, I would not disallow all ICMP. Fragmentation is inherent in IPSec tunnels and hosts will attempt to perform MTU path discovery. Allowing "unreachables" will allow this to work. Or configure all servers behind the VPN with lower MTUs so that fragmentation does not cause performance issues.

-Shannon

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