BGP Community Quetion

[lamav]

Hi, everyone:

Im receiving a community string from my ISP, but I dont know if this is going to impact anything. Im not honoring it anyway....

I asked them about it, and the tech said he couldnt figure out why I was seeing what I am seeing below:

R-2#sh ip bgp 4.23.113.0

BGP routing table entry for 4.23.113.0/24, version 5319341

Paths: (2 available, best #1, table default)

Flag: 0x9C0

Advertised to update-groups:

1

4323 174 21889

66.195.223.25 from 66.195.223.25 (168.215.52.225)

Origin IGP, localpref 100, valid, external, best

Community: 283312179 283312629 283313132 283314631 283362128 4266460140 4266524676 4266590210 4266656045

4323 174 21889

64.13.44.104 (metric 11) from 64.13.44.104 (64.13.44.104)

Origin IGP, metric 0, localpref 100, valid, internal

R-2#

He says he is not sending me any community attributes.

What exactly do those strings mean? Im a bit rusty with my BGP Community knowledge...been a while.

Should I worry about this? Any thoughts?

Thanks, folks

[Richard Burts · Accepted solution]

Victor

The values put into the community strings are arbitrary. If you are seeing them then someone generated them. Just because they are there does not mean that you need to do anything with them.

I do not think that you should worry about them.

HTH

Rick

[Edison Ortiz]

What exactly do those strings mean?

Those are values used within the ISP for traffic engineering.

Per your output, you are looking at those values with the old BGP format.

If you enter the command ip bgp new-format in your router config you will see the values in an aa:nn format which are more meaningful.

HTH,

__

Edison.