troubleshooting Question

BGP inbound for Class C - Preferences Not Taking Effect

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Dealer_SolutionsFlag for Australia asked on
RoutersNetworking ProtocolsInternet Protocols
8 Comments1 Solution396 ViewsLast Modified:
Hi all,

I have a class C public IP range that was allocated from Apnic.
ISP A = 40 Mb fibre connection
ISP B = 40 Mb fibre connection
Behind both ISP's connections we have a cisco 2801 router
Each router gets a default route only via BGP
Each router advertises our public IP range via BGP to the ISP's

We are attempting to preference ISP A over ISP B to get most of the traffic flowing over the preferred provider.

We have tried the following:

Item                                      ISPA                   ISPB
prepending                           None Set           6 x prepended paths
local pref                              Set to 300          Set to 100
local pref via community      Set to 100          Set to 90
MED                                      Set to 50            Set to 350

None of this works - we still get almost all traffic coming into ISPB connection.

Can anyone offer any suggestions on what we would need to do to get some of the traffic from ISPB to ISPA.
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