http://ddos.arbornetworks.com/2009/02/ahh-the-ease-of-introducing-global-routing-instability/ A weblog dedicated to educating the community on security threats that matter Sun, 29 Jan 2012 02:23:23 +0000 hourly 1 http://wordpress.org/?v= http://ddos.arbornetworks.com/2009/02/ahh-the-ease-of-introducing-global-routing-instability/comment-page-1/#comment-201704 blogger » Blog Archive » How a small company caused Internet disruption Tue, 24 Mar 2009 18:26:29 +0000 http://asert.arbornetworks.com/?p=754#comment-201704 [...] Arbor Networks , noted in a blog post that the problem was the result of some versions of Cisco IOS not allocating enough buffer space "for silly long" AS paths. "So they blow chunks when they receive the update," such as the one announced by [...] [...] Arbor Networks , noted in a blog post that the problem was the result of some versions of Cisco IOS not allocating enough buffer space "for silly long" AS paths. "So they blow chunks when they receive the update," such as the one announced by [...]

]]> http://ddos.arbornetworks.com/2009/02/ahh-the-ease-of-introducing-global-routing-instability/comment-page-1/#comment-200769 My Freaky Mind » Peering between SK and ISAT down regarding new bugs from Cisco router. Wed, 18 Mar 2009 04:29:31 +0000 http://asert.arbornetworks.com/?p=754#comment-200769 [...] And also read news from Arbor Networks: [...] [...] And also read news from Arbor Networks: [...]

]]> http://ddos.arbornetworks.com/2009/02/ahh-the-ease-of-introducing-global-routing-instability/comment-page-1/#comment-197424 Internet und tönerne Füße « Impressionen Tue, 24 Feb 2009 00:06:44 +0000 http://asert.arbornetworks.com/?p=754#comment-197424 [...] erwies sich als lösbar und mittlerweile gibt es sogar einen Workaround. Es bleibt jedoch ein fahler Nachgeschmack, denn so stabil wie das Internet zu sein scheint, ist es nicht. Immerhin geschieht so etwas nicht [...] [...] erwies sich als lösbar und mittlerweile gibt es sogar einen Workaround. Es bleibt jedoch ein fahler Nachgeschmack, denn so stabil wie das Internet zu sein scheint, ist es nicht. Immerhin geschieht so etwas nicht [...]

]]> http://ddos.arbornetworks.com/2009/02/ahh-the-ease-of-introducing-global-routing-instability/comment-page-1/#comment-197003 Ivan Pepelnjak Fri, 20 Feb 2009 22:08:01 +0000 http://asert.arbornetworks.com/?p=754#comment-197003 It was a previously unknown IOS bug. The preventive measure has been available for years and should have been used by everyone but was obviously not. See <a href="http://blog.ioshints.info/2009/02/oversized-as-paths-cisco-ios-bug.html" rel="nofollow">Oversized AS paths: Cisco IOS bug details</a>. It was a previously unknown IOS bug. The preventive measure has been available for years and should have been used by everyone but was obviously not. See Oversized AS paths: Cisco IOS bug details.

]]> http://ddos.arbornetworks.com/2009/02/ahh-the-ease-of-introducing-global-routing-instability/comment-page-1/#comment-196757 Long BGP AS paths causing commotion | BGPmon.net Blog Thu, 19 Feb 2009 05:46:30 +0000 http://asert.arbornetworks.com/?p=754#comment-196757 [...] AS47868 was prepending it’s AS path many times, up to 252 times resulting in a AS path of 256. Although this is an insanely high number, considering that the average AS path length is about 4.3, It should definitely not cause the behavior we observed Monday. A number of routers that apparently run older software, were not capable to handle these long AS paths and as a result a fair number of BGP sessions started to flap, which caused a wave of updates (many times higher then normal) causing instability. A Good technical explanations can be found at renesys and arbor security. [...] [...] AS47868 was prepending it’s AS path many times, up to 252 times resulting in a AS path of 256. Although this is an insanely high number, considering that the average AS path length is about 4.3, It should definitely not cause the behavior we observed Monday. A number of routers that apparently run older software, were not capable to handle these long AS paths and as a result a fair number of BGP sessions started to flap, which caused a wave of updates (many times higher then normal) causing instability. A Good technical explanations can be found at renesys and arbor security. [...]

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