Hey Jeff,

In access-list 102 I think you will have to allow echo reply from any
network going to x.x.54.0 and x.x.55.0 or you will not be able to ping any
host on the internet. I see that you have echo reply from "access-list 102
permit icmp host x.x.x.x any echo-reply" if this is the only machine you
want a echo reply from then disregard previous statement. 

On access-list 101, you are not allowing tcp or udp going outbound? What
will do you transport layer stuff? 

Don't know if this helps.... Might even confuse you more......

Scott


-----Original Message-----
From: Jeff [mailto:[EMAIL PROTECTED]]
Sent: Monday, November 26, 2001 11:34 AM
To: [EMAIL PROTECTED]
Subject: ACL Gurus [7:27361]


Looking to block icmp-echo on my external router... just want to doublecheck
that I'm putting these on the right interfaces. Please, suggestions welcome!

Cheers,
Jeff
access-list 101 permit icmp x.x.54.0 0.0.0.255 any echo

access-list 101 permit icmp x.x.55.0 0.0.0.255 any echo

*Permits internal network to ping any host

access-list 101 permit ip any any

*Permits any other traffic to and from the network. Need for the explicit
deny



access-list 102 permit icmp host x.x.x.x any echo-reply

*Permits a ping reply from ISP servers for monitoring

access-list 102 permit icmp any any packet-too-big

*Permits Fragmentation Required ICMP packets (Used of MTU-PD)

access-list 102 deny   icmp any any echo-reply

deny any echo reply from any other sources



access-list 102 deny   icmp any x.x.54.0 0.0.0.255 echo

access-list 102 deny   icmp any x.x.55.0 0.0.0.255 echo

deny any echo from any other sources

access-list 102 permit ip any any

*Permits any other traffic to and from the network. Needed due to the
explicit deny rule.



Both Access-list are applied to the Serial Interfaces of the Edge router.
Access list 102 is assigned to inbound traffic and Access list 101 is
assigned to outbound traffic. See below..



Internet (same ISP, different BGP peers)



S0/0               S0/1

   \                      /

    \                    /

     \                  /

      Edge Router

              |

           E0/0

              |

           FW

              |

           LAN

x.x.54.0 and x.x.55.0 networks




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