slow Transition 03 to exch2010 1

[techseek]

Hello all
small network 30 users. two 08 dc's and exch 03 (member)server.
I'd like to be able to test mailbox moves and mail routing prior to doing the actual users.
1)If I install exch10(on 08R2) and specify legacy url etc but don't make changes to my MX records (Postini), will my exch 03 continue to work as if nothing happened or, does the fact that you specify legacy url during install, force you to make the mx record changes in order to get mail and send mail?
2)What are the most likely problems I can expect to encounter with mailbox moves?
and, is it easy to "roll back" a failed Mailbox move

I will be doing the moves slowly over a period of weeks since I will only be working on fridays after everyone goes home and some mailboxes are 5-6 gigs and I expect will take some time to move.

thanks for any input /guidance

 

[ShackDaddy]

Specifying the legacy URL will not cause any problems and there will be no need to change any public DNS records at that point. Actually, I usually do this migration a little differently and completely ignore the legacy URL. I publish 443 on an alternate public IP address to the new server and use a host file on an external workstation to test OWA/OA/ActiveSync access to the new server with a couple of pilot mailboxes moved over.

Failed mailbox moves usually happen because of corrupted items in the source mailbox. Since you can't fix those corruptions, the best practice is to tell the system to skip 49 corrupted items (max allowable in GUI) when doing the mailbox move. That will allow your migration to work regardless of a handful of corrupted items in a mailbox. It's easy to move a mailbox back to the source server, as long as you remember to delete the earlier move request for that mailbox from the "Move Requests" section of the Exchange Console.

Dave Shackelford
ThirdTier.net
TrainSignal.com

 

[techseek]

Hello Shack
thank you for replying. I am happy to hear that my 03 can continue doing it's thing
until I change mx record. I am not clear on the legacy url related changes that need to be done (I'm no exch expert by any stretch). The suggestion you gave sounds like a great way to test. I would however need to understand what I am doing better to try it. right now, we are just at the point of purchasing hardware and software.
By the way, I'm going with 16 gig memory - does that sound good for our small # of users?

 

[ShackDaddy]

You know, in my book, those legacy URL settings are only for environments that have too many users to be able to cut over the whole company in one weekend. They are intended for a coexistence scenario in which you publish the new server on OWA but want the new server to be able to redirect OWA to the old server for mailboxes that haven't been migrated.

When I do a migration (and I've done about 30 of these 2003-2010 ones) I don't use the legacy URLs at all unless there is going to be a week/month during which some mailboxes live on one server and some on the other. When I do a pilot group test, normally I pick some users that don't access their mailboxes from outside the office, that way having their mailbox on the new server doesn't disrupt their mail access, but I can still use their mailboxes for testing using that extra external IP address up until the time of the real cutover, during which all mailboxes are moved.

That memory should be fine. But it's about the minimum that I would recommend.

Dave Shackelford
ThirdTier.net
TrainSignal.com

 

[techseek]

Thanks so much for your help.
Since it will be my first go at it, I am a bit apprehensive about doing all at once.
I would probably schedule for a 3-day weekend but everything has to be working by that tuesday morning and I feel if I run into problems (which is always expected) I would be in a bind.
How long does it take to move a fairly large MB (6 gigs for example)?

 

[ShackDaddy]

The normal range of data moved per hour is between 3gb and 6gb, so I'd expect your move to take 30-60 minutes. But so much of move time depends on the read-speed on the source server disk, the network latency and other factors.

Once thing I would warn you about: since the move generates transaction logs that match the amount of data being moved, you may consider enabling circular logging on your source server if you are tight on disk space on the drive where your logs are, since you should expect to generate 30gb of log files there during the move. Once you enable circular logging on your database, you'll want to restart the Information Store service to make that change stick.

Let me know if you have other questions. Glad to help make you more comfortable with the process.

Dave Shackelford
ThirdTier.net
TrainSignal.com

 

[techseek]

Hello!
wow, I see. well, we have 30 users, about a dozen are 1gig-6gig in size
Good info to know about the log creation.
One thing i cannot get my head around is the changes in dns/mx etc I need to make
and howlong it will take for those to take effect so I can test things

 

[ShackDaddy]

Why do you need to make any changes at all? Currently your MX records point to Postini. That won't change.

Postini points to an IP at your site. That doesn't have to change. All you need to change is your firewall rule so that ports 25/443 start being directed to the new server at the time of the cutover. Prior to that, all inbound mail can come in through your Exchange 2003 server, which will route it to the Exchange 2010 server just fine.

The only thing you need to do is:

1) Get a multi-named cert for your new server that includes the current public name of your old server (mail.domain.com or something like that) plus another name: autodiscover.domain.com. Additionally I would add the full internal FQDN of your new server (EX2010.domain.local or something like that) to the cert as well.

2) Create an A-record for Autodiscover that points to the IP that you use for mail. You could create it today and it wouldn't disrupt anything.

Dave Shackelford
ThirdTier.net
TrainSignal.com

 

[techseek]

hello
I have to ask, how the exchange 2003 knows to route to exch 2010
what i understand from reading is that once the mx record points to exch10, then exch10 routes to exch03 for mailboxes that reside there??

 

[ShackDaddy]

The same way that a user whose mailbox is on E2003 can email a user on the E2010 server: there is a two-way routing connector that gets mail to the right mailboxes. It doesn't matter whether the mail is delivered initially to the old server or the new one. I still don't think you will need to change MX records at all.

Dave Shackelford
ThirdTier.net
TrainSignal.com

 

[techseek]

hi
so when you mention "the cutover" are you referring to the time when all mailboxes have been moved over? At that time, I would have to change my postini "inbound server"
IP since Exch10 server will have a different one than Exch03. If I do that, I suppose I would also have to put in place the firewall rules for HTTPS as you mention. Does the 2-way routing connector get created during setup or is that a manual process?

 

[ShackDaddy]

Then two-way connector gets created automatically when you install Exchange 2010 into your Exchange 2003 environment.

My general practice is to make as few changes to the outside config as possible, so if it were me I would not be changing Postini to point to a new IP, I'd just tell the firewall "stop forwarding port 25 to the old server's internal IP and start sending it to the new server's internal IP". Because routing is independent of where mailboxes are, you could do that at the beginning of the migration or the end: it wouldn't really matter. What matters more is where port 443 is pointed: I usually swing that port on the firewall from one internal IP to the other once most of the users have been moved over to the new server: that's the main network change that you make on the weekend of the mailbox moves. You will want to add the autodiscover record in your public DNS, but you wouldn't touch MX records and you don't really need to touch Postini's config: you can publish the new server on an alternate IP for testing, but you'd use your normal IP for the actual cutover as I laid out earlier. That way you KNOW that the server is accepting inbound mail on port 25 and you KNOW that OWA is working properly, but you wait till the cutover time to actually push it into production with a firewall change.

There may be a difference between my perspective (which takes into account that you only have 30 users) and the documentation you have been reading (which has to be true for 5000 users as equally as 50), but my advice is based on having migrated more than a hundred small businesses from one version of Exchange to another in the last few years. It's pretty much all I do, and I'm outlining my "simplest solution" here, the one with the least moving parts and smallest margin for error.

Dave Shackelford
ThirdTier.net
TrainSignal.com

 

[techseek]

shackdaddy
thank you for continuing to explain - I really appreciate it
I think part of the problem for me which leads to my confusion is this:
-I have limited Exch "migration" experience and going from Exc5.5 to Exch03 was very easy. Exch10 is a different situation.
-We have never had SSL protection and it's never been an issue
-I mention that to say that I've never had to deal with firewall configs for 443 forwarding etc. I do not know routers and our Internet provider maintains the router - we don't touch it ourselves - I don't know what the config looks like for smtp etc.
I know there is a nat mapping to the internal address of our exch03 server in there.
I don't really have a perspective, I just want to be very clear on the process before I go do it. Your suggestions sound great! And, to be clear, I am opting for coexistence and moving mailboxes over a period of maybe 3-4 months.

 

[ShackDaddy]

What's the total size of your mailbox data? How big is the database?

Dave Shackelford
ThirdTier.net
TrainSignal.com

 

[techseek]

hello
we don't have a huge db it's about 50 G however, I asked around to get a rough estimate of the time it takes to move larger mb's and I'd rather struggle thru the coexistence (as a convenience and because I think I'll learn more).

 

[Zelandakh]

Co-ex is a good plan. You'll be doing offline moves so do a few at a time once you've confirmed connectors work to route mail internally and externally. Remember that a move generates a load of log files so backups are important.

Don't do things blind - understand what you are doing and why...it is far more fun.

Ask stuff here - pertinent questions of course - Dave's been doing this for a lot of years.

 

[ShackDaddy]

Are you using RPC-over-HTTP connectivity for any of your users? Do any use Outlook to connect to your office from the outside?

Zelandakh, I'm asking him this because I know there were issues with the proxying of those connections back to an Exchange 2003 server through the newer Exchange CAS role when it was sharing a server with the Mailbox role. I know this was an issue that made coexistence more difficult with Exchange 2007 and am wondering if that was ever worked out with Exchange 2010.

If it turns out that's still the case, then the users I'd move to the new server first would be the ones who access their mailboxes remotely the most, especially those who use Outlook to do so.

Dave Shackelford
ThirdTier.net
TrainSignal.com

 

[techseek]

hello
sick day yesterday :-(
Just saw postings today. The only access is through owa (only a handful of theusers)
and thru a few cellphones (activesynch).

 

[ShackDaddy]

Ok, so if you want to do successful and simple coexistence, I would be trying to move those ActiveSync and OWA users first, so that you can publish the new server on port 443 and not worry so much about the Legacy urls and http proxy/redirects between the two servers.

You are going to need to get a public certificate (the Exchange 2010 console has a wizard for generating a cert request), and you'll want to have a list of firewall changes for your ISP to make at certain times.

It may be helpful and efficient if you could hire a consultant for an hour or so to look at your configuration, just to validate that everything was set up properly, to help provision the certificate, or to help you move through the actual transition.

Dave Shackelford
ThirdTier.net
TrainSignal.com

 

[techseek]

Hello
I'm gettin close to doing my change over to 2010 Exch.
I have just re-read this thread and it's making more sense to me now.
I thank you all for your help.
I was wondering if the mailbox move auto creates the mailboxes on the 2010 server or if they need to be created manually?
and, how are archive pst's handled?

thanks