Search Again: Re: MX records and new mail servers From: AHC list member Date: Wednesday, September 18, 2002 Time: 2:29:13 pm Chris, thanks for the response... On Wednesday, September 18, 2002, at 04:00 PM, QuickDNS Talk wrote: >> Hey everyone, >> >> The time has come to where we have grown beyond serving on one box. >> Up until this point, I've run a primary and secondary DNS, along >> with Webstar 4.4 on two servers. One server took the brunt of our >> load, running http, ftp and pop for several years. With massive >> increases in mail traffic over the past 12 months, it's really grown >> beyond time to separate off at least the mail services to the second >> machine. We did such over the weekend, adding in all of the >> existing accounts from the primary server (we'll call .5) to the >> other server (.6) >> >> Webstar's mail has a bonus feature of supporting webmail, so during >> the transition from one box to the other, any straggler messages >> that came to .5 could be picked up via browser if the DNS for that >> individual's ISP had already updated and was directing POP requests >> to the new server (all old accounts on .5 have been left active). >> To make sure we didn't bounce anything, we set up MX records like so: >> >> mydomain.com MX 10 new.mail.server >> mydomain.com MX 20 old.mail.server > > That wasn't necessary. If some other mail server has mail for one of > your domains, either it has the old MX record cached or it gets the > new one. Either way, the second MX record you added isn't going to > affect anything (unless your new mail server goes down - redundancy > can be a good thing if done properly). having the old server as our backup will be important. I have some background on how to make it a secondary -- had hoped setting MX priorities would have assisted in that... > >> After all entries were completed, both of our DNS servers were >> restarted. >> >> Updating the DNS was simple enough, and for most of my customers, >> the transition went without a hitch. >> >> However, for two domains, and one email account on one domain, after >> nearly 60 hours, their POP clients continue to be pointed to the old >> server. > > What DNS server are they using for lookups? Have the users of these > two domains tried rebooting? I had them reboot with the same effect. so we went with plan B below > >> Their mail is being successfully collected on the new server. Both >> of the domains in question are served by two separate DSL carriers >> in North Carolina -- so I'm hoping their DNS systems are simply kind >> of slothish. However, the oddity is that the one email account POP >> client from one of our domains continues to go to the old server (it >> is a list serve POP account) while all other POP accounts for the >> same domain -- and all email from the outside, is properly routed to >> the new mail server. Very weird, as that list server lives under >> our roof, and has other list accounts which check the new server >> without issue for the same domain! > > Check your DNS records for the domain in question, and check the > listserv's configuration to see if it's maybe gotten an IP address or > old hostname in the configuration for this list. the list serve indeed had an ip address rather than a pop server name, thx. > >> Anyone have any ideas? Would I be better off removing the second MX >> record from each zone for a while and somehow forcing the clients to >> relookup to the new server on recalcitrant individual accounts or >> zones? (Boy, I hate the thought of re-entering them. > > You should definitely remove the second MX record for the moment, > since the old mail server isn't configured properly as a relay server > for these domains - instead, it considers itself the final > destination for all of your domains. The second mail server can also be shut down to force the issue until we program it as a forwarding server... I've got that writeup around here somewhere... > >> A second question: if I want to run the old server as a backup mail >> server, but don't want it to see any traffic to speak of unless the >> primary mail server goes down, what are the recommended MX priority >> settings? > > What you quoted above will work fine, once the old mail server is > configured to relay all mail for your domains to the new server. > >> I've currently set the MX records as stated above, but don't know >> the benefit of raising the value to 100, or 1000, or whatever. I >> tried 65000 for one zone, but my version of QDNS 3.0.1 gave funky >> errors (a negative number in the record) until I dropped it back >> down to 1000 on that test. Is this value like the load balancing >> numbers, where it is a ratio of hits rather than a fall-over order? > > No. MX records are designed to allow fail over service. Check your > favorite DNS reference for details on how this works. thanks Chris. paul

Messages In This Thread: Re: MX records and new mail servers by AHC list member on Sep 18, 2002 at 2:29:13 pm