Why does BGP Local-Pref show up when using AS-SET option with

From: Riapolov, Bradley (BRiapolo@wm.com)
Date: Sun Aug 26 2007 - 14:56:38 ART


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