Oh where, oh where has Comcast gone

John R Levine johnl at iecc.com
Tue Jun 24 05:21:47 UTC 2003

I saw a bunch of mail to comcast.net bouncing, so I figured I'd check to
see if maybe their mail servers were misconfigured or something.  Holy
petunias, they've imploded into private network space.

It appears that the glue records in the GTLD servers are OK, but ns02 is
returning the 172.30 address which, since it's authoritative for itself,
overwrites the good data.  Tsk, tsk.  I suppose that's one way to cut down
the amount of spam they get.

$ dnsqr ns comcast.net
2 comcast.net:
76 bytes, 1+2+0+0 records, response, noerror
query: 2 comcast.net
answer: comcast.net 4929 NS ns01.jdc01.pa.comcast.net
answer: comcast.net 4929 NS ns02.jdc01.pa.comcast.net

$ dnsqr a ns01.jdc01.pa.comcast.net
1 ns01.jdc01.pa.comcast.net:
59 bytes, 1+1+0+0 records, response, noerror
query: 1 ns01.jdc01.pa.comcast.net
answer: ns01.jdc01.pa.comcast.net 4923 A

$ dnsqr a ns02.jdc01.pa.comcast.net
1 ns02.jdc01.pa.comcast.net:
59 bytes, 1+1+0+0 records, response, noerror
query: 1 ns02.jdc01.pa.comcast.net
answer: ns02.jdc01.pa.comcast.net 4919 A

John Levine, johnl at iecc.com, Primary Perpetrator of "The Internet for Dummies",
Information Superhighwayman wanna-be, http://iecc.com/johnl, Sewer Commissioner
"More Wiener schnitzel, please", said Tom, revealingly.

More information about the NANOG mailing list