[Help] BGP advertise single host

[thanhletrung85]

Dear all experts,

I want to advertise single host via BGP.

I tried 

config network   edit 1     set prefix 10.10.10.10 255.255.255.255   next end

But not succeed.

Anyone know how to advertise single host via BGP?

Thanks and regards

[stanislav_timofeev]

Hi. 

The very possible reason is that by default BGP doesn't advertise routes if they are not in routing table. 

You may check it by #get router info routing-table all 

For your case you should have specific route for  10.10.10.10/32 and then it will be advertised via BGP.

You can create it as a blackhole if you have route for network where your host exists (/24 subnet or other) or simply do following: 

config router bgp  set network-import-check disable end

[journeyman]

Old thread, exactly same question.

I already realised my advertised host IP did not match the routing table so I created a blackhole route, but after that traffic is not forwarded by the matching policy because `reverse check fail, drop` ie the source IP matches the blackhole route and not the larger route associated with the incoming interface, I think. Which makes sense, I guess.

I would really prefer to avoid using `network-import-check disable` as I think this will break dynamic routing.

Is there a neat way to get this to work, or have I missed something basic?