nanog mailing list archives
Re: Memory leak cause of Comcast DNS problems
From: Daniel Golding <dgolding () burtongroup com>
Date: Mon, 18 Apr 2005 13:13:49 -0400
Several of the servers that were down are not BIND, at least these: prospero:~/Desktop/fpdns-0.9.1 dgold$ ./fpdns.pl 68.87.66.196 fingerprint (68.87.66.196, 68.87.66.196): Cisco CNR I ran fpdns against them between outages. They now respond differently. prospero:~/Desktop/fpdns-0.9.1 dgold$ ./fpdns.pl 68.87.66.196 fingerprint (68.87.66.196, 68.87.66.196): q0r?1,IQUERY,0,0,1,1,0,0,REFUSED,0,0,0,0 These are the Comcast "national" DNS servers. (I am using plural, because there are several reverse DNS entries for this IP address - ns.cmc.co.denver.comcast.net and ns.inflow.pa.bo.comcast.net) I wouldn't rush to blame BIND for this. For purposes of investigation, does anyone have DNS servers from those periods of downtime other than the ones above? Comcast is quite a patchwork, that's to the incomplete integrations of MediaOne, AT&T Broadband, etc. It would be interesting to see data on other DNS servers during the downtime periods. Many folks on various forums were suggesting the use of ns1. And ns2.level3. Of course, logic suggests that the vast majority of folks, having no Internet access, could not have read the advice. ---- There have been three explanations given for the outage - 1) Upgrade issues 2) Memory leak/software issue 3) DDoS There is also the possibility of some combination of the above. There are a number of possible permutations. - Dan On 4/17/05 2:18 PM, "Steven M. Bellovin" <smb () cs columbia edu> wrote:
In message <20050417.100203.11740.378954 () webmail23 lax untd com>, "Fergie (Paul Ferguson)" writes:Not to my knowledge, or at least, none that has been publicly acknowledged.From a Washington Post article yesterday (posted via Yahoo!News), Comcast said that the problem manifested itself when they were in the process of upgrading their DNS servers:
http://story.news.yahoo.com/news?tmpl=story&ncid=1212&e=3&u=/washpost/2005041>> 6
/tc_washpost/a56223_2005apr15&sid=96168964At least in my neighborhood, Comcast appears to be running BIND 9.2.4rc6 --Prof. Steven M. Bellovin, http://www.cs.columbia.edu/~smb
-- Daniel Golding Network and Telecommunications Strategies Burton Group
Current thread:
- Re: Memory leak cause of Comcast DNS problems, (continued)
- Re: Memory leak cause of Comcast DNS problems Florian Weimer (Apr 17)
- Re: Memory leak cause of Comcast DNS problems Eric A. Hall (Apr 17)
- Re: Memory leak cause of Comcast DNS problems David Conrad (Apr 17)
- Re: Memory leak cause of Comcast DNS problems Eric A. Hall (Apr 17)
- Re: Memory leak cause of Comcast DNS problems Eric A. Hall (Apr 17)
- Re: Memory leak cause of Comcast DNS problems Eric Brunner-Williams in Portland Maine (Apr 18)
- Re: Memory leak cause of Comcast DNS problems Fergie (Paul Ferguson) (Apr 17)
- Re: Memory leak cause of Comcast DNS problems Florian Weimer (Apr 17)
- Re: Memory leak cause of Comcast DNS problems Fergie (Paul Ferguson) (Apr 17)
- Re: Memory leak cause of Comcast DNS problems Steven M. Bellovin (Apr 17)
- Re: Memory leak cause of Comcast DNS problems Martin J. Levy (Apr 17)
- Re: Memory leak cause of Comcast DNS problems Daniel Golding (Apr 18)
- Re: Memory leak cause of Comcast DNS problems Florian Weimer (Apr 18)
- Re: Memory leak cause of Comcast DNS problems Jason Frisvold (Apr 18)
- Re: Memory leak cause of Comcast DNS problems Steven M. Bellovin (Apr 17)
- Re: Memory leak cause of Comcast DNS problems Florian Weimer (Apr 17)
- Re: Memory leak cause of Comcast DNS problems Christopher L. Morrow (Apr 17)