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</o:shapelayout></xml><![endif]--></head><body lang=EN-CA link=blue vlink=purple style='word-wrap:break-word'><div class=WordSection1><p class=MsoNormal><span style='mso-fareast-language:EN-US'>Does anyone have info whether this network </span><span style='mso-fareast-language:EN-US'>69.171.240.0/20 was reachable during the outage.<o:p></o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'>Jean</span><span style='mso-fareast-language:EN-US'><o:p></o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'><o:p> </o:p></span></p><div style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0cm 0cm 0cm'><p class=MsoNormal><b><span lang=EN-US>From:</span></b><span lang=EN-US> NANOG <nanog-bounces+jean=ddostest.me@nanog.org> <b>On Behalf Of </b>Tom Beecher<br><b>Sent:</b> October 5, 2021 10:30 AM<br><b>To:</b> NANOG <nanog@nanog.org><br><b>Subject:</b> Re: Facebook post-mortems...<o:p></o:p></span></p></div><p class=MsoNormal><o:p> </o:p></p><div><blockquote style='border:none;border-left:solid #CCCCCC 1.0pt;padding:0cm 0cm 0cm 6.0pt;margin-left:4.8pt;margin-right:0cm'><p class=MsoNormal>People keep repeating this but I don't think it's true.<o:p></o:p></p></blockquote><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>My comment is solely sourced on my direct observations on my network, maybe 30-45 minutes in. <o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Everything except a few /24s disappeared from DFZ providers, but I still heard those prefixes from direct peerings. There was no disaggregation that I saw, just the big stuff gone. This was consistent over 5 continents from my viewpoints.<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Others may have seen different things at different times. I do not run an eyeball so I had no need to continually monitor. <o:p></o:p></p></div></div><p class=MsoNormal><o:p> </o:p></p><div><div><p class=MsoNormal>On Tue, Oct 5, 2021 at 10:22 AM Niels Bakker <niels=<a href="mailto:nanog@bakker.net">nanog@bakker.net</a>> wrote:<o:p></o:p></p></div><blockquote style='border:none;border-left:solid #CCCCCC 1.0pt;padding:0cm 0cm 0cm 6.0pt;margin-left:4.8pt;margin-right:0cm'><p class=MsoNormal>* <a href="mailto:telescope40@gmail.com" target="_blank">telescope40@gmail.com</a> (Lou D) [Tue 05 Oct 2021, 15:12 CEST]:<br>>Facebook stopped announcing the vast majority of their IP space to <br>>the DFZ during this.<br><br>People keep repeating this but I don't think it's true.<br><br>It's probably based on this tweet: <br><a href="https://twitter.com/ryan505/status/1445118376339140618" target="_blank">https://twitter.com/ryan505/status/1445118376339140618</a><br><br>but that's an aggregate adding up prefix counts from many sessions. <br>The total number of hosts covered by those announcements didn't vary <br>by nearly as much, since to a significant extent it were more specifics <br>(/24) of larger prefixes (e.g. /17) that disappeared, while those /17s <br>stayed.<br><br>(There were no covering prefixes for WhatsApp's NS addresses so those <br>were completely unreachable from the DFZ.)<br><br><br> -- Niels.<o:p></o:p></p></blockquote></div></div></body></html>