nanog mailing list archives
Some doubts on large scale BGP/AS design and black hole routing risk
From: "magicboiz () hotmail com" <magicboiz () hotmail com>
Date: Thu, 31 Mar 2016 10:12:07 +0200
Hi everybody!as part of laboratory work at the university, I'm working on a BGP design study, and I would like to post some questions regarding IP address space allocation and its impact on BGP which are breaking my mind :)
Let's suppose we have an ISP/AS with two POPs: PARIS and LONDON. These two POPs are connected with redundant leased lines. Each POP has a BGP router speaking eBGP to different ISP providers/upstreams and also, each POP run its own OSPF area/ISIS area. Something like this:
<INET> ---eBGP---<LONDON POP-ospf area1>===redundant leased lines (ospf area0)===<PARIS POP- ospf area2>---eBGP---<INET>
Now, this AS/ISP gets one /22 prefix from it RIR (RIPE in this case), and starts to announce it to its upstreams in PARIS and LONDON at the same time.
My questions are:1. What could happen in the case of total failure in the redundant leased lines? Black hole routing between POPs?
2. What are the best design methods to avoid this scenario?2.1: adding a third POP creating a triangle? What if a POP looses connection with the other two POPs at the same time? Another black hole?
2.2: requesting another prefix and allocating 1:1 prefix:POP, so in the scenario each POP only would announce its prefix to the upstreams?
2.3: other? Thanks in advance! J.
Current thread:
- Some doubts on large scale BGP/AS design and black hole routing risk magicboiz () hotmail com (Apr 03)
- Re: Some doubts on large scale BGP/AS design and black hole routing risk Mark Tinka (Apr 03)
- Re: Some doubts on large scale BGP/AS design and black hole routing risk Christopher Morrow (Apr 04)
- Re: Some doubts on large scale BGP/AS design and black hole routing risk Mark Tinka (Apr 04)
- Re: Some doubts on large scale BGP/AS design and black hole routing risk magicboiz () hotmail com (Apr 04)
- Re: Some doubts on large scale BGP/AS design and black hole routing risk Christopher Morrow (Apr 04)
- Re: Some doubts on large scale BGP/AS design and black hole routing risk Mark Tinka (Apr 04)
- Re: Some doubts on large scale BGP/AS design and black hole routing risk joel jaeggli (Apr 05)
- Re: Some doubts on large scale BGP/AS design and black hole routing risk Christopher Morrow (Apr 04)
- Re: Some doubts on large scale BGP/AS design and black hole routing risk Hank Nussbacher (Apr 04)
- Re: Some doubts on large scale BGP/AS design and black hole routing risk Mark Tinka (Apr 03)
- <Possible follow-ups>
- Re: Some doubts on large scale BGP/AS design and black hole routing risk Scott Weeks (Apr 04)