Server to new server transfer

[iway]

Hello!

I have one Ubuntu 8.0.4 LTS 64bit server with NE 5.0.9 running at our location. I want to move the server to a new one hosted at a datacenter. Since transfering the full backup (approx. 70GB) over our 5mbps line takes much too long, I thought about doing it this way:

I make a full backup on the old server. With the old server still running and serving users, I transfer that backup to the new server. This may take 2 days...
When the transfer is finished, I stop access to the old server completely and make a final incremental backup. This should transfer much quicker, reducing overall downtime.
After all incrementals have transfered, I run a zmrestoreoffline on the new server (the new server now has the full backup and all following incrementals from the last 2 days). Then the new server can go online, the old one is turned off since the last incremental.

That should do it, shouldn't it?

Any thoughts on that or other ideas?

Thanks a lot!

Chris

[iway]

I'll just answer myself: We did it that way now and it seems to be OK. Hope it stays that way...

[taneks]

Hi,

Am planning to do the same thing. Can you please share with us some of steps involved in the migration?

Many thanks.

Steven

[iway]

Sure!

It was really not that easy... We basically followed the Wiki (Network Edition: Moving from 32-bit to 64-bit Server - Zimbra :: Wiki). The problem: Just adjusting the passwords in the localconfig.xml file was not enough. After some frustrating hours we tried zmldappasswd with all options to set all ldap passwords (amavis, postfix, etc.) again to the old server values. That fixed it.

Another problem: We had the server running on 4GB RAM with about 50 concurrent users. That brought the server down, it was not responding any more. We then set vm.swappiness to 0 and put 8GB of RAM in. Since then it worked much better. Hope it stays that way, keep my fingers crossed...
The swappiness seems to have a huge impact here.

Good luck!
I don't want to do it again...
But once it is done, all seems better. 64bit memory handling is much better, the server responsiveness might have improved, too.

[taneks]

Thanks for the quick reply. I guess I had better run a trial migration first. We just started using Zimbra as a trial with a few users, but word got out and our test server became production too quickly.

[iway]

Yes, definitely make a trial run first!