BGP Community String for Eunet Finland AS6667

Tweet

Attention

This BGP Community string information might be outdated. Please contact Eunet Finland AS6667 to get more recent one. This BGP communites is ONLY for the customer who has BGP with Eunet Finland AS6667. www.ipbalance.com is not maintaining this BGP Community string.

These BGP communities are recognized and used by AS6667

NOTE: These BGP communities will evolve with changes in transit providers and exchange points. If you are having problems with the BGP communities, check here first to see if a BGP community has been changed or removed. We will try to not change the meaning of a BGP community unless the new meaning is a direct replacement.

The BGP communities that set the local preference within our network are usable by all customers and peers. The default local preference for customers is 101 and for peers it is 100. The default local preference for transits is 90. Local preference of 80 is meant for backup provided by a customer or peer to someone else and the local preference of 110 is meant for overriding routing to choose a certain path over others. Peers can’t set a preference of 110.

Local Preference

 

BGP Community String	font size="2">Description
6667:80	Set LOCAL_PREF to 80
6667:90	Set LOCAL_PREF to 90
6667:100	Set LOCAL_PREF to 100
6667:110	Set LOCAL_PREF to 110

 

The BGP communities that control route announcement to peers and transits are only available to customers. The x specifies what the action for the said target is:

 

 

We will also let external BGP communities through from customers. This will enable customers to use similar BGP communities of our peers and transits. Some pages describing these BGP communities have been collected at the end of the page.

 

BGP Community String	Description
6667:90x	to all AS6667 customers
6667:100x	to all transits
6667:101x	to AS3356 Level3
6667:102x	to AS3549 Global Crossing
6667:103x	to AS3320 T-Systems
6667:200x	to all peers
6667:201x	to peers in Helsinki Finland and at Ficix
6667:202x	to peers in Stockholm Sweden and at Netnod
6667:203x	to peers in London United Kingdom and as LINX
6667:204x	to peers in Frankfurt Germany and at DECIX
6667:205x	to peers in Hamburg Germany
6667:206x	to peers in Copenhagen Denmark and at DIX
6667:207x	to peers in Oslo Norway and at NIX
6667:208x	to peers in Amsterdam The Netherlands and at AMS-IX
6667:209x	to peers in New York USA and at NYIIX

 

 

These BGP communities are tagged on all routes to distinguish their origins. They are sent to everyone but not excepted from outside. They are there to let customers filter routes based on route source.

A normal customer announces all their routes to us with BGP communities 6667:900, 6667:1000 and 6667:2000. When Eunet receives the routes, they are tagged with 6667:300x and the local location BGP community string(6667:4xxx.)

Route Origins

 

BGP Community String	Description
6667:3000	Internal or customer
6667:3001	public peering
6667:3003	private peering
6667:3004	Transit
6667:4000	Tampere Finland
6667:4001	Turku, Finland
6667:4002	Helsinki, Finland
6667:4003	Stockholm,Sweden
6667:4004	London United Kingdom
6667:4005	Frankfurt, Germany
6667:4006	Hamburg, Germany
6667:4007	Copenhagen, Denmark
6667:4008	Oslo, Norway
6667:4009	Amsterdam The Netherlands
6667:4010	New York, USA

 

 

 

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 BGP 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 [ISP AS]:120 or [ISP AS]:3 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-ISP] permit 10
router(config-route-map)#match ip address 10
router(config-route-map)#set community [ISP AS]:120 <—- using Local Preference

or

router(config-route-map)#set community [ISP AS]:3 <——- using AS prepending
router(config-route-map)#route-map [to-ISP] 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-ISP] 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.