Re: [isp-bgp] ACL not honoured for route advertisement.

[Arnold Nipper <arnold@...>]

On 30.12.2004 00:41 mb@....au wrote

> I am attempting to limit advertisements to one of our upstreams - but the ACL 
> is not being honoured:
>
> neighbor Connect_Open_Pipe distribute-list UNLIMITED_PREFIXES_OUT out
>
> #sh ip access-lists UNLIMITED_PREFIXES_OUT            
> Standard IP access list UNLIMITED_PREFIXES_OUT
>     permit 203.149.70.0, wildcard bits 0.0.0.255 (2 matches)
>     permit 203.149.69.0, wildcard bits 0.0.0.255 (2 matches)
>     permit 203.149.72.0, wildcard bits 0.0.0.255 (5 matches)
>     permit 203.149.64.0, wildcard bits 0.0.15.255 (12 matches)
>     permit 203.23.194.0, wildcard bits 0.0.0.255 (5 matches)
>     deny   any log (151086 matches)
>
>
> #sh ip bgp neighbors Connect_Open_Pipe advertised-routes 
> BGP table version is 7115144, local router ID is 210.10.54.92
> Status codes: s suppressed, d damped, h history, * valid, > best, i - internal
> Origin codes: i - IGP, e - EGP, ? - incomplete
>
>    Network          Next Hop            Metric LocPrf Weight Path
> *> 203.23.194.0     0.0.0.0                  0         32768 i
> *> 203.149.64.0/20  0.0.0.0                  0         32768 i
> *> 203.149.66.0     0.0.0.0                  0         32768 i
> *> 203.149.71.0     203.149.67.66            0         32768 i
> *> 203.149.72.0     203.149.66.62            0         32768 i
>
> I am only concerned with the 203.149.66.0/24 and 203.149.71.0/24 networks - I 
> do not want them advertised to this upstream (I want them only to be 
> advertised to our other upstream - More attractive route than the entire /20 
> so traffic destined for those to /24's *should* come in via the other 
> upstream).
Use prefix list which gives more clearness and are much faster. That means:

ip prefix-list UNLIMITED_PREFIXES_OUT seq 10 permit 203.23.194.0/24
ip prefix-list UNLIMITED_PREFIXES_OUT seq 20 permit 203.149.64.0/20
ip prefix-list UNLIMITED_PREFIXES_OUT seq 30 permit 203.149.69.0/24
ip prefix-list UNLIMITED_PREFIXES_OUT seq 40 permit 203.149.70.0/24
ip prefix-list UNLIMITED_PREFIXES_OUT seq 50 permit 203.149.72.0/24

If you are only concerned about 203.149.66.0/24 and 203.149.71.0/24 you 
might also want to write:

ip prefix-list UNLIMITED_PREFIXES_OUT seq 10 deny 203.149.66.0/24
ip prefix-list UNLIMITED_PREFIXES_OUT seq 20 deny 203.149.71.0/24
ip prefix-list UNLIMITED_PREFIXES_OUT seq 30 permit 203.149.64.0/20 le 24




Arnold
--
Arnold Nipper, AN45





To unsubscribe via postal mail, please contact us at:
Jupitermedia Corp.
Attn: Discussion List Management
475 Park Avenue South
New York, NY 10016

Please include the email address which you have been contacted with.

Copyright 2004 Jupitermedia Corporation All Rights Reserved.