nanog mailing list archives
Re: BGP Route Issues
From: Fakrul Alam Pappu <fakrulalam () gmail com>
Date: Mon, 19 Aug 2013 18:27:08 +0600
Won't it be backslash rather than forward slash? _([0-9]+) _\1_\1_\1_ On Mon, Aug 19, 2013 at 9:51 AM, Randy <randy_94108 () yahoo com> wrote:
11 prepends is beyond-excessive besides being annoying. filter please _([0-9]+) _/1_/1_/1_________________________________ From: Blake Dunlap <ikiris () gmail com> To: Christopher Karel <chris.karel () gmail com> Cc: "nanog () nanog org" <nanog () nanog org> Sent: Sunday, August 18, 2013 7:42 PM Subject: Re: BGP Route Issues Local Pref (which is common by the way to be set so customers > peers > transit). AS Path doesn't beat it. You can only request people follow the routes you want ingress, there's nothing you can do to force them to take a path to you short of deaggregation, and that only works until they notice it, and it irratates the rest of the world as well by using additional route slots. Poor routing is purely a viewpoint problem, not necessarily in agreement between all parties. -Blake On Sun, Aug 18, 2013 at 8:33 PM, Christopher Karel <chris.karel () gmail com wrote:Good evening, I'm hoping you guys might be able to offer some advice or insightintoa BGP problem I've got. I've noticed some strange routes between our network, AS27270, and AS22943. It looks like both our networks are dual homed. One ISP as the primary, and the other used as a backup, withpathprepending to prevent it from actually being used except in an outage. However, our route to 22943 appears to be using their backup link.(272704323 7018 22943 22943 22943 22943 22943 22943 22943 22943 22943 22943 22943) Which is strange, because we can reach their primary ISP without any such rigmarole. Playing around with Looking Glass servers indicates that Cogent (AS174) has a similar backup route to our network. (174 22402 272702727027270 27270 27270 27270) Everywhere else I check seems perfectly sane. But since Cogent is essentially in-between the two networks I'm troubleshooting, I would assume that the other network has a similarroute.But Cogent won't talk with me about this, since I'm not a customer. So as far as advice goes, is there a common issue that might resultinsuch poor routes in both directions? Any further troubleshooting that I should be doing? Or any ideas on how to help remedy things that appeartobe outside our network/ISP? Or are we doing something so wrong thatthisis all my fault? I'd really appreciate any input on this.
Current thread:
- BGP Route Issues Christopher Karel (Aug 18)
- Re: BGP Route Issues Blake Dunlap (Aug 18)
- Re: BGP Route Issues Randy (Aug 18)
- Re: BGP Route Issues Fakrul Alam Pappu (Aug 19)
- Re: BGP Route Issues Nick Hilliard (Aug 19)
- Re: BGP Route Issues Randy (Aug 19)
- Re: BGP Route Issues Randy (Aug 18)
- Re: BGP Route Issues Blake Dunlap (Aug 18)
- Re: BGP Route Issues Seth Mattinen (Aug 18)