[100677] in North American Network Operators' Group
RE: BGP Peering and Prefix filterin Question
daemon@ATHENA.MIT.EDU (Jim McBurnett)
Sun Nov 4 17:38:51 2007
From: Jim McBurnett <jim@tgasolutions.com>
To: Warren Kumari <warren@kumari.net>
CC: "nanog@nanog.org" <nanog@nanog.org>
Date: Sun, 4 Nov 2007 17:34:10 -0500
In-Reply-To: <0D8DE8E6-EEA9-4401-AF90-760715D21D32@kumari.net>
Errors-To: owner-nanog@merit.edu
--_000_CCD4153D830F584982521DFC986BFF3111F914DAtgainf06TGASolu_
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Well,
You are correct on the translation---
Finally heard back from all players.
And someone "properly" summarized the prefixes.
Initially they were sent as 4 /24's due to data center disparity and a rout=
e policy.
But in the end someone at the 1st upstream summarized the routes to their u=
pstreams.
And when the 1st upstream realized they should not be summarizing and chang=
ed that- their upstreams blocked the traffic.
Go figure..
Thanks for the input guys!
Jim
From: Warren Kumari [mailto:warren@kumari.net]
Sent: Monday, October 29, 2007 3:54 PM
To: Jim McBurnett
Cc: nanog@nanog.org
Subject: Re: BGP Peering and Prefix filterin Question
I'm suspecting that the customers problem was BGP Flap Damping (or Dampenin=
g) and that somehow the explanation got lost in translation somewhere (I've=
tried explaining it to some non-engineers sometimes and it is a tricky con=
cept for many to grasp for some reason...)
Whether its "normal" or a good idea or who does / doesn't do it is a topic =
fraught with religion....
Warren
On Oct 29, 2007, at 2:15 PM, Jim McBurnett wrote:
Hello,
Recently I have been told that some ISP's are automatically or maybe manual=
ly modifying their BGP inbound prefix listing after a network is not advert=
ised to them for a period of time.
So the questions I pose to the group:
1. Is this normal?
2. Can anyone share your policies?
3. Who does it?
4. How often?
5. Is it automagic? Or the dirty work slaved off to the junior engine=
er in the corner somewhere?
a. I know you probably won't trust that junior engineer, but some do.=
...
Anyway just a little research after a small problem a customer recently had=
.
Thanks,
Jim
--
She'd even given herself a middle initial - X - which stood for "someone wh=
o has a cool and exciting middle name".
-- (Terry Pratchett, Maskerade)
--_000_CCD4153D830F584982521DFC986BFF3111F914DAtgainf06TGASolu_
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<div class=3DSection1>
<p class=3DMsoNormal><span style=3D'font-size:11.0pt;font-family:"Calibri",=
"sans-serif";
color:#1F497D'>Well,<o:p></o:p></span></p>
<p class=3DMsoNormal><span style=3D'font-size:11.0pt;font-family:"Calibri",=
"sans-serif";
color:#1F497D'>You are correct on the translation---<o:p></o:p></span></p>
<p class=3DMsoNormal><span style=3D'font-size:11.0pt;font-family:"Calibri",=
"sans-serif";
color:#1F497D'>Finally heard back from all players.<o:p></o:p></span></p>
<p class=3DMsoNormal><span style=3D'font-size:11.0pt;font-family:"Calibri",=
"sans-serif";
color:#1F497D'>And someone “properly” summarized the prefixes.<=
o:p></o:p></span></p>
<p class=3DMsoNormal><span style=3D'font-size:11.0pt;font-family:"Calibri",=
"sans-serif";
color:#1F497D'>Initially they were sent as 4 /24’s due to data center=
disparity
and a route policy.<o:p></o:p></span></p>
<p class=3DMsoNormal><span style=3D'font-size:11.0pt;font-family:"Calibri",=
"sans-serif";
color:#1F497D'>But in the end someone at the 1<sup>st</sup> upstream summar=
ized
the routes to their upstreams.<o:p></o:p></span></p>
<p class=3DMsoNormal><span style=3D'font-size:11.0pt;font-family:"Calibri",=
"sans-serif";
color:#1F497D'>And when the 1<sup>st</sup> upstream realized they should no=
t be
summarizing and changed that- their upstreams blocked the traffic.<o:p></o:=
p></span></p>
<p class=3DMsoNormal><span style=3D'font-size:11.0pt;font-family:"Calibri",=
"sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=3DMsoNormal><span style=3D'font-size:11.0pt;font-family:"Calibri",=
"sans-serif";
color:#1F497D'>Go figure..<o:p></o:p></span></p>
<p class=3DMsoNormal><span style=3D'font-size:11.0pt;font-family:"Calibri",=
"sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=3DMsoNormal><span style=3D'font-size:11.0pt;font-family:"Calibri",=
"sans-serif";
color:#1F497D'>Thanks for the input guys!<o:p></o:p></span></p>
<p class=3DMsoNormal><span style=3D'font-size:11.0pt;font-family:"Calibri",=
"sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=3DMsoNormal><span style=3D'font-size:11.0pt;font-family:"Calibri",=
"sans-serif";
color:#1F497D'>Jim<o:p></o:p></span></p>
<p class=3DMsoNormal><span style=3D'font-size:11.0pt;font-family:"Calibri",=
"sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<div>
<div style=3D'border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0in =
0in 0in'>
<p class=3DMsoNormal><b><span style=3D'font-size:10.0pt;font-family:"Tahoma=
","sans-serif"'>From:</span></b><span
style=3D'font-size:10.0pt;font-family:"Tahoma","sans-serif"'> Warren Kumari
[mailto:warren@kumari.net] <br>
<b>Sent:</b> Monday, October 29, 2007 3:54 PM<br>
<b>To:</b> Jim McBurnett<br>
<b>Cc:</b> nanog@nanog.org<br>
<b>Subject:</b> Re: BGP Peering and Prefix filterin Question<o:p></o:p></sp=
an></p>
</div>
</div>
<p class=3DMsoNormal><o:p> </o:p></p>
<div>
<div>
<p class=3DMsoNormal>I'm suspecting that the customers problem was BGP Flap
Damping (or Dampening) and that somehow the explanation got lost in transla=
tion
somewhere (I've tried explaining it to some non-engineers sometimes and it =
is a
tricky concept for many to grasp for some reason...)<o:p></o:p></p>
</div>
<div>
<p class=3DMsoNormal><o:p> </o:p></p>
</div>
<div>
<p class=3DMsoNormal>Whether its "normal" or a good idea or who d=
oes /
doesn't do it is a topic fraught with religion....<o:p></o:p></p>
</div>
<div>
<p class=3DMsoNormal><o:p> </o:p></p>
</div>
<div>
<p class=3DMsoNormal>Warren<o:p></o:p></p>
</div>
<div>
<p class=3DMsoNormal><o:p> </o:p></p>
</div>
<div>
<p class=3DMsoNormal><o:p> </o:p></p>
</div>
<div>
<p class=3DMsoNormal><o:p> </o:p></p>
</div>
<div>
<p class=3DMsoNormal>On Oct 29, 2007, at 2:15 PM, Jim McBurnett wrote:<o:p>=
</o:p></p>
</div>
<p class=3DMsoNormal><br>
<br>
<o:p></o:p></p>
<div>
<p class=3DMsoNormal style=3D'mso-margin-top-alt:auto;mso-margin-bottom-alt=
:auto'><span
class=3Dapple-style-span><span style=3D'font-size:11.0pt;font-family:"Calib=
ri","sans-serif";
color:black'>Hello,</span></span><span style=3D'color:black'><o:p></o:p></s=
pan></p>
<p class=3DMsoNormal style=3D'mso-margin-top-alt:auto;mso-margin-bottom-alt=
:auto'><span
class=3Dapple-style-span><span style=3D'font-size:11.0pt;font-family:"Calib=
ri","sans-serif";
color:black'>Recently I have been told that some ISP’s are automatica=
lly or
maybe manually modifying their BGP inbound prefix listing after a network i=
s
not advertised to them for a period of time.</span></span><span
style=3D'color:black'><o:p></o:p></span></p>
<p class=3DMsoNormal style=3D'mso-margin-top-alt:auto;mso-margin-bottom-alt=
:auto'><span
class=3Dapple-style-span><span style=3D'font-size:11.0pt;font-family:"Calib=
ri","sans-serif";
color:black'> </span></span><span style=3D'color:black'><o:p></o:p></s=
pan></p>
<p class=3DMsoNormal style=3D'mso-margin-top-alt:auto;mso-margin-bottom-alt=
:auto'><span
class=3Dapple-style-span><span style=3D'font-size:11.0pt;font-family:"Calib=
ri","sans-serif";
color:black'>So the questions I pose to the group:</span></span><span
style=3D'color:black'><o:p></o:p></span></p>
<p class=3DMsoListParagraph style=3D'text-indent:-.25in'><span
class=3Dapple-style-span><span style=3D'font-size:11.0pt;font-family:"Calib=
ri","sans-serif";
color:black'>1.</span></span><span class=3Dapple-style-span><span
style=3D'font-size:7.0pt;color:black'> =
</span></span><span
class=3Dapple-style-span><span style=3D'font-size:11.0pt;font-family:"Calib=
ri","sans-serif";
color:black'>Is this normal?</span></span><span style=3D'font-size:11.0pt;
font-family:"Calibri","sans-serif";color:black'><o:p></o:p></span></p>
<p class=3DMsoListParagraph style=3D'text-indent:-.25in'><span
class=3Dapple-style-span><span style=3D'font-size:11.0pt;font-family:"Calib=
ri","sans-serif";
color:black'>2.</span></span><span class=3Dapple-style-span><span
style=3D'font-size:7.0pt;color:black'> =
</span></span><span
class=3Dapple-style-span><span style=3D'font-size:11.0pt;font-family:"Calib=
ri","sans-serif";
color:black'>Can anyone share your policies?</span></span><span
style=3D'font-size:11.0pt;font-family:"Calibri","sans-serif";color:black'><=
o:p></o:p></span></p>
<p class=3DMsoListParagraph style=3D'text-indent:-.25in'><span
class=3Dapple-style-span><span style=3D'font-size:11.0pt;font-family:"Calib=
ri","sans-serif";
color:black'>3.</span></span><span class=3Dapple-style-span><span
style=3D'font-size:7.0pt;color:black'> =
</span></span><span
class=3Dapple-style-span><span style=3D'font-size:11.0pt;font-family:"Calib=
ri","sans-serif";
color:black'>Who does it?</span></span><span style=3D'font-size:11.0pt;
font-family:"Calibri","sans-serif";color:black'><o:p></o:p></span></p>
<p class=3DMsoListParagraph style=3D'text-indent:-.25in'><span
class=3Dapple-style-span><span style=3D'font-size:11.0pt;font-family:"Calib=
ri","sans-serif";
color:black'>4.</span></span><span class=3Dapple-style-span><span
style=3D'font-size:7.0pt;color:black'> =
</span></span><span
class=3Dapple-style-span><span style=3D'font-size:11.0pt;font-family:"Calib=
ri","sans-serif";
color:black'>How often?</span></span><span style=3D'font-size:11.0pt;font-f=
amily:
"Calibri","sans-serif";color:black'><o:p></o:p></span></p>
<p class=3DMsoListParagraph style=3D'text-indent:-.25in'><span
class=3Dapple-style-span><span style=3D'font-size:11.0pt;font-family:"Calib=
ri","sans-serif";
color:black'>5.</span></span><span class=3Dapple-style-span><span
style=3D'font-size:7.0pt;color:black'> =
</span></span><span
class=3Dapple-style-span><span style=3D'font-size:11.0pt;font-family:"Calib=
ri","sans-serif";
color:black'>Is it automagic? Or the dirty work slaved off to the junior
engineer in the corner somewhere?</span></span><span style=3D'font-size:11.=
0pt;
font-family:"Calibri","sans-serif";color:black'><o:p></o:p></span></p>
<p class=3DMsoListParagraph style=3D'margin-left:1.0in;text-indent:-.25in'>=
<span
class=3Dapple-style-span><span style=3D'font-size:11.0pt;font-family:"Calib=
ri","sans-serif";
color:black'>a.</span></span><span class=3Dapple-style-span><span
style=3D'font-size:7.0pt;color:black'> =
</span></span><span
class=3Dapple-style-span><span style=3D'font-size:11.0pt;font-family:"Calib=
ri","sans-serif";
color:black'>I know you probably won’t trust that junior engineer, bu=
t some do….</span></span><span
style=3D'font-size:11.0pt;font-family:"Calibri","sans-serif";color:black'><=
o:p></o:p></span></p>
<p class=3DMsoNormal style=3D'mso-margin-top-alt:auto;mso-margin-bottom-alt=
:auto'><span
class=3Dapple-style-span><span style=3D'font-size:11.0pt;font-family:"Calib=
ri","sans-serif";
color:black'> </span></span><span style=3D'color:black'><o:p></o:p></s=
pan></p>
<p class=3DMsoNormal style=3D'mso-margin-top-alt:auto;mso-margin-bottom-alt=
:auto'><span
class=3Dapple-style-span><span style=3D'font-size:11.0pt;font-family:"Calib=
ri","sans-serif";
color:black'>Anyway just a little research after a small problem a customer
recently had.</span></span><span style=3D'color:black'><o:p></o:p></span></=
p>
<p class=3DMsoNormal style=3D'mso-margin-top-alt:auto;mso-margin-bottom-alt=
:auto'><span
class=3Dapple-style-span><span style=3D'font-size:11.0pt;font-family:"Calib=
ri","sans-serif";
color:black'> </span></span><span style=3D'color:black'><o:p></o:p></s=
pan></p>
<p class=3DMsoNormal style=3D'mso-margin-top-alt:auto;mso-margin-bottom-alt=
:auto'><span
class=3Dapple-style-span><span style=3D'font-size:11.0pt;font-family:"Calib=
ri","sans-serif";
color:black'> </span></span><span style=3D'color:black'><o:p></o:p></s=
pan></p>
<p class=3DMsoNormal style=3D'mso-margin-top-alt:auto;mso-margin-bottom-alt=
:auto'><span
class=3Dapple-style-span><span style=3D'font-size:11.0pt;font-family:"Calib=
ri","sans-serif";
color:black'>Thanks,</span></span><span style=3D'color:black'><o:p></o:p></=
span></p>
<p class=3DMsoNormal style=3D'mso-margin-top-alt:auto;mso-margin-bottom-alt=
:auto'><span
class=3Dapple-style-span><span style=3D'font-size:11.0pt;font-family:"Calib=
ri","sans-serif";
color:black'>Jim</span></span><span style=3D'color:black'><o:p></o:p></span=
></p>
</div>
<p class=3DMsoNormal><span style=3D'font-size:9.0pt;font-family:"Helvetica"=
,"sans-serif";
color:black'><br>
<br>
</span><o:p></o:p></p>
</div>
<p class=3DMsoNormal><o:p> </o:p></p>
<div>
<div>
<p class=3DMsoNormal><span style=3D'font-size:9.0pt;font-family:"Helvetica"=
,"sans-serif";
color:black'>--<o:p></o:p></span></p>
</div>
<div>
<p class=3DMsoNormal><span style=3D'font-size:9.0pt;font-family:"Helvetica"=
,"sans-serif";
color:black'>She'd even given herself a middle initial - X - which stood fo=
r
"someone who has a cool and exciting middle name".<o:p></o:p></sp=
an></p>
</div>
<div>
<p class=3DMsoNormal><span style=3D'font-size:9.0pt;font-family:"Helvetica"=
,"sans-serif";
color:black'><o:p> </o:p></span></p>
</div>
<div>
<p class=3DMsoNormal><span style=3D'font-size:9.0pt;font-family:"Helvetica"=
,"sans-serif";
color:black'> <span class=3Dapple-converted-space> </span>=
--
(Terry Pratchett, Maskerade)<o:p></o:p></span></p>
</div>
<p class=3DMsoNormal><span style=3D'font-size:9.0pt;font-family:"Helvetica"=
,"sans-serif";
color:black'><br>
<br>
</span><o:p></o:p></p>
</div>
<p class=3DMsoNormal><o:p> </o:p></p>
</div>
</body>
</html>
--_000_CCD4153D830F584982521DFC986BFF3111F914DAtgainf06TGASolu_--
