From: SIMON HART (simon.hart@btinternet.com)
Date: Tue May 24 2005 - 11:06:59 GMT-3
Hi,
The BGP table shows that the network 10.6.0.0/15 has been summarised on this router. If you look at the configuration on this router you will see the following (or something akin to it)
aggregate-address 10.6.0.0 255.254.0.0
Incidentally you can identify that the sumarisation occurred on this router as the Local Pref is set to 32768 and the next hop is 0.0.0.0
The brackets show the AS Paths of the networks that fall under this summarisation. In this situation you will note that 10.6.0.0/16 has been learnt from both 64951 and 64953 . So in your BGP table these two As's are added to the the aggregate address.
These As paths will be advertised to a neighboring eBGP peer if the as-set argument is added to the aggregate address command. Otherwise the AS path of the advertising router will be sent to an eBGP peer
HTH
Simon
D.Tropiano@sirtisistemi.it wrote:
Hi Group,
could someone tell me the meaning of the brackets in the Path of network
10.6.0.0/15:
sh ip bgp vpnv4 vrf TIMNET
BGP table version is 1815, local router ID is 172.31.120.2
Status codes: s suppressed, d damped, h history, * valid, > best, i -
internal,
S Stale
Origin codes: i - IGP, e - EGP, ? - incomplete
Network Next Hop Metric LocPrf Weight Path
Route Distinguisher: 10:20 (default for vrf TIMNET)
* 10.2.1.0/30 10.13.1.251 40 0 64951 ?
*>i 172.31.184.1 30 100 0 64951 ?
* 10.2.7.0/24 10.13.1.251 40 0 64951 ?
*>i 172.31.184.1 30 100 0 64951 ?
* 10.2.13.0/24 10.13.1.251 40 0 64951 ?
*>i 172.31.184.1 30 100 0 64951 ?
* 10.2.14.0/30 10.13.1.251 40 0 64951 ?
*>i 172.31.184.1 30 100 0 64951 ?
* 10.3.2.0/30 10.13.1.251 40 0 64951 ?
*>i 172.31.184.1 30 100 0 64951 ?
* 10.3.26.0/30 10.13.1.251 40 0 64951 ?
*>i 172.31.184.1 30 100 0 64951 ?
* 10.3.45.0/24 10.13.1.251 40 0 64951 ?
*>i 172.31.184.1 30 100 0 64951 ?
s> 10.6.0.0/16 10.13.1.251 40 0 64951 ?
s i 172.31.184.1 100 0 64953 ?
Network Next Hop Metric LocPrf Weight Path
*> 10.6.0.0/15 0.0.0.0 100 32768 {64951,64953}
?
* i 172.31.120.1 0 100 0 {64951,64953}
?
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