Changing web/mail host and minimizing downtime

March 10, 2010 2:39 AM

How can i change my web/mail host the easiest way and also minimize any downtime?

I've recently grown unsatisfied with my current web host, mostly because of limitations, downtime and increasing price without any perceivable gains. So I've found another highly recommended host i wanna move to, but there are some obstacles in the way which make me kinda worried.
Basically my site is just a Wordpress blog and some other small sub sites, which are all easily backed up and I made a database dump as well, I think it would be the easiest to move. Also it's nothing critical so even if I mess up, I wouldn't care since Wordpress is easy to set up again.

My big worry are my email accounts, which i have 5 of, all hosted on my own domain on this host. I don't exactly understand how i can move these to my new host while avoiding any downtime. My biggest concern is that during this move someone will send me an mail which will be undeliverable or something and I wouldn't know it happened.

I think I understand the basic DNS of it, and that it takes some time for the servers to update to my new host. I have the possibility to keep both sites up at the same time, so would it be possible to create the mail accounts on my new host even if i don't have the domain transferred right away? Or do i have to wait until the domain has been transferred? And can I really avoid any downtime or is it inevitable?

Thanks in advance

posted by kampken to Computers & Internet (9 answers total)

Best answer: I think I understand the basic DNS of it, and that it takes some time for the servers to update to my new host.

Yes. Anything up to 48 hours is often quoted. But you may see the change within a much shorter time.

I have the possibility to keep both sites up at the same time, so would it be possible to create the mail accounts on my new host even if i don't have the domain transferred right away?

Absolutely. You should be able to configure your domain and set up all your email accounts at the new host so that it's ready to handle email for your domain as soon as the DNS has propagated. Both your old and new hosts will be able to recieve email for the domain - which host an email goes to will depend on how far the DNS change has propagated at a given time.

You haven't said what you use as a mail client. Assuming you're using something like Thunderbird or Outlook, you can just set up a second account which checks the new host's mail server. Then you can check both accounts for a few days until you're sure that everything's going to the new host. If the mail server name for your old host is something like 'mail.yourdomain.com' you may need to change this so that it uses your host's mail server name (which could be something like 'mail1234.youroldhost.com') instead. Ask your old host what settings you should use once your domain is no longer associated with the hosting account - they should be able to help.

If, on the other hand, you use some sort of webmail at your old host, you should simply be able to set up an auto-forward to send your mail to a gmail or hotmail account, which is probably the easiest way to avoid losing anything.
posted by le morte de bea arthur at 3:07 AM on March 10, 2010

Response by poster: Just to clarify I'm using a mix of Thunderbird/Outlook/webmail.

Thanks le morte de bea arthur, that's very helpful. It makes more sense now..I just have to think about it as being transitional and if the mails doesn't pop in at one place, it's probably just does in the other place.
posted by kampken at 3:30 AM on March 10, 2010

You should also be able to set up your old mail host to forward mails to your new one using the name@[ip.address.numbers.here] format.
posted by flabdablet at 3:39 AM on March 10, 2010

I moved a slew of sites from one server. I ended up using google apps for the email, and I'd seriously consider doing the same. It is great and free (although paid versions are available).

Google gives you a temporary email, so you can set up the accounts first, then forward a copy of all mail on the old server to the respective google apps temporary email.

Should result in a seamless switch.
posted by backwards guitar at 4:21 AM on March 10, 2010

Response by poster: Alright, I've started the transfer now. Created mail accounts on the new hosts, the website came over with no problems (just needed to change database settings) and waiting for the DNS switch now. I've decided to forward all mails on the old host to webmail accounts to be sure i don't miss anything.

Thanks for the help all :)
posted by kampken at 5:23 AM on March 10, 2010

LMdBA is right on the money, though checking the old host "for a few days" is a bit optimistic, in my experince.

I say don't kill the old mail host until you're certain it's "empty". Wait until there's no activity (no mail seems to be going there anymore at all) and then wait another week to be sure.

(Your own tests might work right away, but you can't control the dns/routing/caches used by others and many ISPs have horrible caches that ignore updates for weeks... people who use the dns servers from those ISPs (most people) will still be sending mail to your old host, and this is "correct" behavior.)

That is, just because the new one is "working for you" that definitely doesn't mean it's working for the whole world yet.
posted by rokusan at 8:01 AM on March 10, 2010

It sounds like you've already started the process, but I want to chime in with some advice that seems to have been left out.

You have a couple of points of control over how long it takes DNS changes to propagate. First, many DNS hosts expose the ability to change the TTL (time to live) which controls how long the result of DNS lookups for your domain are cached. Theoretically these can be set as low as 1s, but usually the smallest increment I've seen exposed is one minute, or one hour. In any case, if you turn this down before you make other changes, you can cut down the cut-over window considerably (though there is always some chance that someone ignores the TTL you set).

If you are also switching the registrar and/or nameserver for your domain, you have another potential source for delays. The mitigation is to set up DNS entries with the new registrar and/or nameserver host that point back to your old host. Then do the registrar and/or nameserver switch. Once that has gone through, you can move your site and update the DNS entries to point to your new host.

Not all DNS hosting gives you access to TTL settings, and not all let you set up DNS records for a domain before you've completed a transfer. In that case you might want to use a separate DNS hosting service transitionally.

The last thing is to keep in mind that you can make changes DNS changes for mail routing (MX records) separately from the A records that point to your webserver.
posted by Good Brain at 9:23 AM on March 10, 2010

You've already started it, but yeah, fire it off on a Friday or at least later in the evening so all the stuff has time to propagate.

I did it with google apps, and my old host changed the MX record pretty much immediately. Within an hour everything was hunky dory.
posted by gjc at 5:43 PM on March 10, 2010

Response by poster: Indeed, I've noticed that on certain DNS servers the change has been completed but others are still lacking..keeping up the old site and mail for some time then.
Also the MX record changes a lot faster than the A record..strange :)
posted by kampken at 11:26 PM on March 10, 2010