[Mailman-Users] old mailserver interfering with new one??

[Paul Tomblin]

Quoting Gretchen at Ladyweave.com | 269-369-1114 (gretchen at ladyweave.com):
> One of my clients has recently switched hosting companies, both of whom use
> Mailman. The new e-mail accounts seem to be working intermittently. When I
> looked into the old server's mailboxes, there seem to be "stray" messages in
> there that were sent after the hosting switch. Is it possible the old
> mailboxes are intercepting messages?

When you switch from one host to another, you have to update your DNS
(Domain Name Service) records to point to the new site.  However, DNS
records have a "TTL" (time to live) which tells clients that they don't
have to look up the record if they already looked it up less than "TTL"
seconds ago.  So they might still be seeing the old pointer instead of the
new one for however long your TTL is set to (1 day is a very common TTL
value).  Additionally, some people insist on using Microsoft clients, and
Microsoft thinks they're smarter than the creators of DNS records, so they
ignore TTL and cache these things for longer than a day.  But in a few
days, it will all sort out and all the mail will be going to the new host.

I recently switched IPs, and 90% of the traffic switched within a few
hours, and all of it had changed in a day, but I have a strict "NO USING
OUTLOOK OR OUTLOOK EXPRESS" rule on most of my mailing lists.  Your
mileage may vary.

-- 
Paul Tomblin <ptomblin at xcski.com> http://blog.xcski.com/
"By the time they had diminished from 50 to 8, the other dwarves began
to suspect 'Hungry' ..."
		-- Gary Larson, "The Far Side"