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Attention

This BGP Community string information might be outdated. Please contact Media Link Ukraine AS16112 to get more recent one. This BGP communites is ONLY for the customer who has BGP with Media Link Ukraine AS16112. www.ipbalance.com is not maintaining this BGP Community string.

 

BGP Community String List

These BGP community string can be set by customers for supressing
advertisement if their announces

By default routes are advertised to all peers with 0 prepends

BGP communities format: 16112:PXX
P — peer code, one of:
1 — Digital Generation (AS13228)
2 — Ukrtelecom (AS6849)
3 — ZP-IX2 (AS30777)
4 — Datacom (AS21219)

XX is:
00 : do not advertise
01 : advertise without prepends
02 : advertise with 1 prepend
03 : advertise with 2 prepends
04 : advertise with 5 prepends

Examples:
16112:101 — Advertise to Digital Generation without prepends
16112:101 16112:204 16112:302 16112:400 — Advertise to Digital
Generation without prepends, advertise to Ukrtelecom with
5 prepends, advertise to ZP-IX2 with 1 prepend and do not
advertise to Datacom.

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For any routing questions mail to [email protected]
Any abuse questions should mail to [email protected]
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Applying BGP Community string with sample configuration

2. Pick the best BGP community string for your traffic shaping plan (mainly incoming traffic). Most of ISPs are providing community string with local preference and AS prepending option. Cannot tell which one is better than the other. It will depend on your global traffic shaping plan.

3. Follow the below commands ( Cisco only )

The below Sample configuration will tag the 10.0.0.0/24 route with 16112:103 and will not tag any other routes.

router#config t
router(config)#ip bgp-community new-format
router(config)#access-list 10 permit 10.0.0.0 0.0.0.255
router(config)#access-list 10 deny any

router(config)#route-map to-AS16112 permit 10
router(config-route-map)#match ip address 10

router(config-route-map)#set community 16112:103 <—— using Local Preference

router(config-route-map)#route-map to-AS16112 permit 20
router(config-route-map)#exit

router(config)#router bgp [xxxx] <—————————- xxxx = customer’s ASN
router(config-router)#neighbor x.x.x.x send-community
router(config-router)#neighbor x.x.x.x route-map to-AS16112 out
router(config-router)#exit
router(config)#exit
router#copy running-config startup-config

4. And then, go to www.RouteServer.org and pick one of route server on the map to see your announcement. If you are using AS prepending option, you will see your AS prepends on route servers. Sometime you might not see your route with particular ISP path.
In most of case it might not be any routing problem, just the route path was dropped at somewhere by BGP best path selection scheme. Try Oregon route server, if you can see your route. The Oregon route server is providing many possible and available paths between BGP speakers and neighbors.
If you don’t see your route on there? check other route servers and also check your
BGP configuration. You might need to contact your upstream provider to check what they are learning BGP route from you.