Routing policies are becoming so complex that a complete description is beyond the scope of this document.
NOTE – RADB generated filters are applied on all peers.
We accept even /32 from most customers.
Anything longer than /24 will not get past our peers.
MACROS IN USE
AS-KQRONIX – KPNQwest Romania transit (to private peers)
AS-KQROTERRA – KPNQwest Romania terestrial customers
AS-KQROSAT – KPNQwest Romania satelit customers
AS-KQROBAK – KPNQwest Romania backed-up customers
LOCAL PREFERENCE TABLE
55 Route received from RoNIX
50 Route received from RDSNet
BGP COMMUNITIES – ROUTE TYPE – NOT SETTABLE FROM EXTERN
5606:2040 Private Peer route
BGP COMMUNITIES – CUSTOMER-SETTABLE
5606:12 Prepend 5606 twice to Private peer
5606:13 Prepend 5606 three times to Private peer
5606:14 Prepend 5606 four times to Private peer
5606:21 Prepend 5606 once to upstream
5606:22 Prepend 5606 twice to upstream
5606:23 Prepend 5606 three times to upstream
5606:66 Block this prefix in the European Backbone (for dDOS attacks)
5606:67 Don’t announce to Private peers
5606:68 Don’t announce to Upstreams
5606:80 Lower local preference to 98
5606:90 Increase local preference to 102
Applying BGP Community string with sample configuration
1. Get the latest BGP community string from your ISP/upstream provider or check www.ShowipBGP.com web site.
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.
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