RE: Took network down with wrong access-list

From: Jake Jake (spage@nc.rr.com)
Date: Thu Nov 14 2002 - 19:41:57 GMT-3


Explicit deny all at the end of access lists (even though its not visible)

Add a second statement (access-list 100 permit ip any any)

This way ICMP will match first statement and be denied, and all other IP
traffic
will be permitted by second statement.

-----Original Message-----
From: nobody@groupstudy.com [mailto:nobody@groupstudy.com]On Behalf Of
Jeongwoo Park
Sent: Thursday, November 14, 2002 5:03 PM
To: 'ccielab@groupstudy.com'
Subject: Took network down with wrong access-list

Hi all.
I like to share what I did this morning to take an internet connection down
for one of customers' companies.

Internet_router#

Interface s0
Ip access-group 100 in
.
.
.
access-list 100 deny icmp any host 172.16.1.10 echo

I was tring to set up access-list in a way that no one can ping one of their
servers in their network.
This config took their internet connection down.
I immediately removed it, and it came back normal.

What did I wrong?

Thanks,

JP



This archive was generated by hypermail 2.1.4 : Tue Dec 03 2002 - 07:23:00 GMT-3