From: CCIE 19999 (ccie@iprimus.com.au)
Date: Sun Aug 26 2007 - 15:33:54 ART
In addition to the local preference, which is 100 by default any way, the
AS-SET also destroys the as-path. See the as path pre-pended the AS# 1 in
the bgp table. I assume, because you have the new as-path set, the
local-preference is displayed in the bgp table output.
Network Next Hop Metric LocPrf Weight Path
*> 3.0.0.0 0.0.0.0 32768 i
*> 3.0.0.0 0.0.0.0 100 32768 1 i
Regards,
Shine
-----Original Message-----
From: nobody@groupstudy.com [mailto:nobody@groupstudy.com] On Behalf Of
Riapolov, Bradley
Sent: Monday, 27 August 2007 3:57 AM
To: ccielab@groupstudy.com
Subject: Why does BGP Local-Pref show up when using AS-SET option with the
aggregate-address command, does anyone know?
Without AS-SET (notice that Local-Pref is missing from sh ip bgp):
############################################
Rack1R1(config-router)#do sh run | b rou
router bgp 1
no synchronization
bgp log-neighbor-changes
network 3.3.3.0 mask 255.255.255.0
network 3.3.4.0 mask 255.255.255.0
neighbor 1.1.1.2 remote-as 2
no auto-summary
Rack1R2(config-router)#do sh run | b rou
router bgp 2
no synchronization
bgp log-neighbor-changes
aggregate-address 3.0.0.0 255.0.0.0
neighbor 1.1.1.1 remote-as 1
no auto-summary
Rack1R2(config-router)#do sh ip bgp
BGP table version is 4, local router ID is 1.1.1.2
Status codes: s suppressed, d damped, h history, * valid, > best, i -
internal,
r RIB-failure, S Stale
Origin codes: i - IGP, e - EGP, ? - incomplete
Network Next Hop Metric LocPrf Weight Path
*> 3.0.0.0 0.0.0.0 32768 i
*> 3.3.3.0/24 1.1.1.1 0 0 1 i
*> 3.3.4.0/24 1.1.1.1 0 0 1 i
Now with AS-SET (Local-Pref automagically appears):
##############################################
Rack1R2(config-router)# aggregate-address 3.0.0.0 255.0.0.0 as-set
Rack1R2(config-router)#do sh ip bgp
BGP table version is 5, local router ID is 1.1.1.2
Status codes: s suppressed, d damped, h history, * valid, > best, i -
internal,
r RIB-failure, S Stale
Origin codes: i - IGP, e - EGP, ? - incomplete
Network Next Hop Metric LocPrf Weight Path
*> 3.0.0.0 0.0.0.0 100 32768 1 i
*> 3.3.3.0/24 1.1.1.1 0 0 1 i
*> 3.3.4.0/24 1.1.1.1 0 0 1 I
This archive was generated by hypermail 2.1.4 : Sat Sep 01 2007 - 11:32:13 ART