Stupid Cisco ACL question

Jay Ford jay-ford at uiowa.edu
Thu Apr 21 14:20:09 CDT 2011


On Thu, 21 Apr 2011, up at 3.am wrote:
> permit tcp any eq 443 any
> permit tcp any eq 80 any
> deny ip any host 2.2.3.4
> permit ip any any
>
> This is applied to an inbound interface(s).  We want anybody outside to be
> able to reach ports 80 and 443 of any host on our network, no matter what,
> then block ALL other access to select hosts, such as 2.2.3.4, even ICMP.
> However, as soon as I apply this rule to the interface, ports 80 and 443
> of that host become unreachable.  A telnet to 2.2.3.4 443 gets "Connection
> refused" until I tear out the deny ACL above.  I even tried adding udp for
> both ports, to no avail.

Your ACL is apply the 80 & 443 as source ports, not destination ports.

You probably want:
    permit tcp any any eq 443
    permit tcp any any eq 80
    deny ip any host 2.2.3.4
    permit ip any any

________________________________________________________________________
Jay Ford, Network Engineering Group, Information Technology Services
University of Iowa, Iowa City, IA 52242
email: jay-ford at uiowa.edu, phone: 319-335-5555, fax: 319-335-2951




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