From: Albert Lu (albert_ccie@xxxxxxxxx)
Date: Sat Dec 01 2001 - 07:03:40 GMT-3
Yes, that is correct. However, you have to note that the AS-SET has no order
like an AS-PATH, so it's just a bunch of AS's that the aggregate was created
from, with no specific order.
I still haven't found a the reason why the aggregate is coming back.
Albert
-----Original Message-----
From: kenairs [mailto:kenairs@hotmail.com]
Sent: Saturday, December 01, 2001 7:47 PM
To: Albert Lu; nlegs@visto.com
Cc: ccielab@groupstudy.com
Subject: Re: BGP Aggregate Route feeding back.
So about using as-set after the aggreate address command. This way AS
information is prepend to the aggreate route advertisment , and R6 will not
accepted the route as R5 and R6 is in the same AS.
Am i correct ?
----- Original Message -----
From: Albert Lu <albert_ccie@yahoo.com>
To: <nlegs@visto.com>
Cc: <ccielab@groupstudy.com>
Sent: Friday, November 30, 2001 8:04 PM
Subject: RE: BGP Aggregate Route feeding back.
> But why is this happening? Shouldn't it see the AS path and not propagate
it
> back to the originator of the summary?
> -----Original Message-----
> From: nlegs@visto.com [mailto:nlegs@visto.com]
> Sent: Friday, November 30, 2001 10:14 PM
> To: ccielab@groupstudy.com; albert_ccie@yahoo.com
> Subject: Re: BGP Aggregate Route feeding back.
>
>
> Try this ...
>
> router bgp 620
> neighbor 216.30.1.4 distribute-list 101 out
>
> access-list 101 deny ip host 172.16.0.0 host 255.255.0.0
> access-list 101 permit ip any any
>
>
>
>
>
> -----Original Message-----
> From: Albert Lu albert_ccie@yahoo.com
> Sent: Fri, 30 Nov 2001 21:44:50 +1100
> To: ccielab@groupstudy.com
> Subject: BGP Aggregate Route feeding back.
>
>
> Hello Group,
>
> I got a problem with BGP aggregate route being advertised out to another
AS,
> and then readvertised back to the original AS through another entry
router.
>
> R5_________R6
> |
> R7
>
> Basically an ethernet segment R5, R6, R7 on the same subnet. R5 & R6 in
> AS600, and R7 in AS500. R5 sends out an aggregate of 172.16.0.0/16 to R7,
> and then somehow R6 learns this aggregate route also.
>
> Configs:
>
> R5#
> router bgp 620
> no synchronization
> bgp router-id 10.10.10.5
> bgp log-neighbor-changes
> bgp confederation identifier 600
> aggregate-address 172.16.0.0 255.255.0.0 as-set suppress-map sup_map
> neighbor 10.10.10.4 remote-as 620
> neighbor 10.10.10.4 update-source Loopback0
> neighbor 10.10.10.7 remote-as 500
> neighbor 10.10.10.7 ebgp-multihop 2
> neighbor 10.10.10.7 update-source Loopback0
> neighbor 10.10.10.7 route-map set_med out
> no auto-summary
> !
>
> BGP table version is 16, local router ID is 10.10.10.5
> 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
> *> 172.16.0.0 0.0.0.0 100 32768 (610) i
> <--------******* Source of aggregate
> s>i172.16.1.0/24 216.30.30.2 0 100 0 (610) i
> s>i172.16.2.0/24 216.30.30.2 0 100 0 (610) i
> s>i172.16.3.0/24 216.30.30.2 0 100 0 (610) i
> *>i172.16.4.0/24 216.30.30.2 0 100 0 (610) i
> *> 192.168.22.0 10.10.10.7 0 500 400 i
> R5#
>
>
> R6#
> router bgp 620
> no synchronization
> bgp router-id 10.10.10.6
> bgp log-neighbor-changes
> bgp confederation identifier 600
> neighbor 10.10.10.4 remote-as 620
> neighbor 10.10.10.4 update-source Loopback0
> neighbor 10.10.10.7 remote-as 500
> neighbor 10.10.10.7 ebgp-multihop 2
> neighbor 10.10.10.7 update-source Loopback0
> neighbor 10.10.10.7 route-map set_med out
> no auto-summary
> !
>
> BGP table version is 24, local router ID is 10.10.10.6
> 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
> *>i172.16.0.0 10.10.10.5 100 0 (610) i
> <--------- Somehow R6 learns it as well
> *>i172.16.1.0/24 216.30.30.2 0 100 0 (610) i
> *>i172.16.2.0/24 216.30.30.2 0 100 0 (610) i
> *>i172.16.3.0/24 216.30.30.2 0 100 0 (610) i
> *>i172.16.4.0/24 216.30.30.2 0 100 0 (610) i
> * i192.168.22.0 10.10.10.7 100 0 500 400 i
> *> 10.10.10.7 0 500 400 i
> R6#
>
> R7#
> router bgp 500
> bgp router-id 10.10.10.7
> bgp log-neighbor-changes
> neighbor 10.10.10.5 remote-as 600
> neighbor 10.10.10.5 ebgp-multihop 2
> neighbor 10.10.10.5 update-source Loopback0
> neighbor 10.10.10.6 remote-as 600
> neighbor 10.10.10.6 ebgp-multihop 2
> neighbor 10.10.10.6 update-source Loopback0
> neighbor 10.10.10.6 route-map change_weight in
> neighbor 10.10.10.8 remote-as 400
> neighbor 10.10.10.8 ebgp-multihop 2
> neighbor 10.10.10.8 update-source Loopback0
> maximum-paths 2
> no auto-summary
> !
>
> BGP table version is 9, local router ID is 10.10.10.7
> 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
> *> 172.16.0.0 10.10.10.5 0 600 i
<--------
> Sent out to R7
> * 10.10.10.5 0 600 i
<--------
> Some how learnt it twice
> *> 172.16.1.0/24 10.10.10.6 150 600 i
> *> 172.16.2.0/24 10.10.10.6 0 600 i
> *> 172.16.3.0/24 10.10.10.6 0 600 i
> *> 172.16.4.0/24 10.10.10.5 50 0 600 i
> * 10.10.10.6 100 0 600 i
> *> 192.168.22.0 10.10.10.8 0 0 400 i
> R7#
>
>
This archive was generated by hypermail 2.1.4 : Thu Jun 13 2002 - 10:32:35 GMT-3