On Mon, Sep 17, 2001 at 10:43:40PM +0000, board master wrote:
> I've recently had a problem sending mail to AOL, MSN, and HOTMAIL. I read
> in the archives about the patch to dns.c. Is it true that this will fix the
> problem?
>
Depends on whether you were really having a problem with large MX
record responses or not -- AFAIK that is the only problem that
particular patch solves. You may or may not have been running into it --
I'm suspicious, though, as I can't see any possible way an MX or ANY
query for msn.com could generate a TCP response:
gregw@bilbo:~$ DNSCACHEIP=BIND.box dnsqr any msn.com
255 msn.com:
476 bytes, 1+10+6+7 records, response, noerror
query: 255 msn.com
answer: msn.com 1083 NS dns1.cp.msft.net
answer: msn.com 1083 NS dns1.tk.msft.net
answer: msn.com 1083 NS dns3.uk.msft.net
answer: msn.com 1083 NS dns3.jp.msft.net
answer: msn.com 1083 NS dns1.dc.msft.net
answer: msn.com 1083 NS dns1.sj.msft.net
answer: msn.com 381 MX 20 smtp-gw-4.msn.com
answer: msn.com 1247 A 207.46.185.39
answer: msn.com 1247 A 207.46.176.152
answer: msn.com 2894 SOA dns.cp.msft.net msnhst.microsoft.com 2001091702
1800 900 7200000 3600
authority: msn.com 1083 NS dns1.cp.msft.net
authority: msn.com 1083 NS dns1.tk.msft.net
authority: msn.com 1083 NS dns3.uk.msft.net
authority: msn.com 1083 NS dns3.jp.msft.net
authority: msn.com 1083 NS dns1.dc.msft.net
authority: msn.com 1083 NS dns1.sj.msft.net
additional: dns1.cp.msft.net 88670 A 207.46.138.20
additional: dns1.tk.msft.net 57122 A 207.46.232.37
additional: dns3.uk.msft.net 60643 A 213.199.144.151
additional: dns3.jp.msft.net 67863 A 207.46.72.123
additional: dns1.dc.msft.net 64335 A 207.68.128.151
additional: dns1.sj.msft.net 57677 A 207.46.97.11
additional: smtp-gw-4.msn.com 1112 A 207.46.181.13
Thinking about this -- dns falls back to TCP when UDP times out, IIRC,
and the dns.c patch _may_ also allow that to work.
>
> I've applied the patch and reinstalled qmail 1.03 and it seems
> like it's working OK now (alhtough I haven't done any massive tests...just a
> few small ones). If it IS true that this fixes that MAJOR qmail problem,
> will it be included in the next version of qmail? Why "shouldn't" I install
> the patch if for any reason at all?
I fail to see this as a MAJOR qmail problem -- the only place I know of
that still actually returns such a large list in response to an ANY
query under normal circumstances is large-mx.ckdhr.com. Under some
circumstances, with a BIND cache, I've seen large responses for aol.com,
but that's easy enough to solve -- don't use a BIND cache. I've never
seen the need for the dns.c patch on a production server -- all of mine
use dnscache. I prefer, myself, to have a pristine qmail source tree --
I have no need for any of the patches.
I'd say its very likely you have been experiencing some other transient
DNS failures, and that was the cause of your problem... As to inclusion
in qmail-2.0, you'll have to wait for word from Dan.
--
Greg White
