On Sat, Dec 4, 2021 at 6:16 AM Alessandro Vesely via mailop <mailop@mailop.org> wrote: > > On Thu 02/Dec/2021 19:55:37 +0100 Brotman, Alex via mailop wrote: > > Folks, > > > > You may or may not have noticed we've been moving some things around. > > We've published new MX records, and have moved traffic over. The old MX > > records will cease to exist shortly. If you're somehow fixated on those > > old MX records or associated IPs, your traffic to comcast.net recipients > > may not work much longer. > > > > Please let us know if you have any questions or concerns. Thanks > > > I get > ;; ANSWER SECTION: > comcast.net. 300 IN MX 5 mx1h1.comcast.net. > comcast.net. 300 IN MX 5 mx2h1.comcast.net. > comcast.net. 300 IN MX 5 mx1a1.comcast.net. > comcast.net. 300 IN MX 5 mx1c1.comcast.net. > comcast.net. 300 IN MX 5 mx2c1.comcast.net. > comcast.net. 300 IN MX 5 mx2a1.comcast.net. > > Are those new or old ones? > > I'm unable to send mail to comcast.net since a couple of days. The server > fails > saying "Did not find a suitable MX for a connection". When I tried manually > mx1h1.comcast.net, the connection was closed before I could type "mail from".
To which IP, and was it over IPv4 or IPv6? Telnet test works fine from here: $ host mx1h1.comcast.net. mx1h1.comcast.net has address 96.102.157.178 mx1h1.comcast.net has IPv6 address 2001:558:fd02:243f::2 aiverson@s1:~$ nc 96.102.157.178 25 220 resimta-h1p-037526.sys.comcast.net resimta-h1p-037526.sys.comcast.net ESMTP server ready (Didn't hang up on me; I did a quick and dirty send test and it worked fine.) I'm assuming the IP is a new/current one based on every public DNS I test showing that as a current IP. If we were waiting out TTLs or if somebody was caching beyond best practices, we'd be getting varying results. https://xnnd.com/dns.cgi?t=mx&d=comcast.net&m=yes I don't use IPv6, so I don't have an easy way to test it today. So if you're coming in on IPv6 and having issues that I'm not having, maybe they have an IPv6 issue or can't resolve your DNS. Or if IPv4, are you sure you're not connecting from an IP considered to be dynamic and/or on lists of IPs that "shouldn't be running mail servers" like the Spamhaus PBL? Cheers, Al -- Al Iverson / Deliverability blogging at www.spamresource.com Subscribe to the weekly newsletter at wombatmail.com/sr.cgi DNS Tools at xnnd.com / (312) 725-0130 / Chicago (Central Time) _______________________________________________ mailop mailing list mailop@mailop.org https://list.mailop.org/listinfo/mailop
