ZxMig vs ZxBackup

[Cine]

Hello ppdeonet,

5GB of exported data, which are ~10GB of actual data, in 6 hours are nowhere near good...
As perfectly analyzed by Trantor, the bottleneck is on the I/O performances of your ferry store (running an `htop` during the export will surely show that the impact on CPU and RAM is minimal).

I'd really follow Trantor's suggestion to directly connect the disk to the SATA bus of the server in order to let the disk work at full speed.

The steps would be:
- Stop Zimbra and shutdown the source server.
- Connect the ferry store to the source server's SATA bus.
- Start the server and mount the new disk.
- Stop the real time scanner, set the backup path to a directory on the ferry store and perform a FullScan operation.
- Stop Zimbra and shutdown the source server.
- Remove the ferry store from the server.
- Start the source server and shutdown the destination server
- Connect the ferry store to the destination server's SATA bus.
- Start the destination server, mount the ferry store and import your data (DO NOT initialize ZeXtras Backup).
- Mount the ferry store through SSHFS on the source server.
- Perform a SmartScan on the source server.
- Switch the mail flow to the destination server.
- Perform a SmartScan on the source server.
- Import again to align the data.

I know it is a long procedure which requires 2 server restarts, but it's the only way to speed up the process...


Keep us up to date with the status of your migration, we'll do our best to help

Have a nice day,
Cine

[Edit: When setting up a new server, always keep in mind the official guidelines posted HERE, they are not strictly related to very large deployments.]

[ppdeonet]

Thanks Cine.
What would be a fair performance in terms of actual data per hour with the ferry store connected to the SATA bus ?
I know you can't give exact figures, but would it be near 10 GB per hour or ~ 100 GB per hour ?
Thanks again,
Perry

[Trantor]

Hello ppdeonet.

Given the performances seen on your system, I'd say somethin between 1 and 5 GiB/h, considering also the 1GB in 15 minutes you've mentioned early.
It's a bit of a stab in the dark event then, anyway I wouldn't bet too much on reaching 10GiB per hour. As Cine mentioned before, however, there's quite a lot of deduplication and compression happening during the export, therefore the amount of data you can see with a du -sh /opt/zimbra/store divided by the transfer rate would not be a realistic estimate of the time required to complete the operation. (PS post the result of du -sh /opt/zimbra/store, just to have an idea of how much data we're talking about).

Trantor

[ppdeonet]

Considering the lack of performance of the live server during export we could only do the export in the weekend.
Seems like we need a very long weekend......

root@deolinux1:/media/usb1# du -sh /opt/zimbra/store
764G /opt/zimbra/store

[ppdeonet]

Tried to use a mirror copy of our Zimbra server to do the migration unfortunately Zimbra does not start on the mirror copy (off the network):
Starting ldap...Done.
Failed. /opt/zimbra/bin/ldap: line 56: kill: (28695) - No such process
Googled around and tried to fix it by - creating new licenses
- setting and fixing permissions
- changing IP and hostname and try on the network
- checking/updating DNS settings (Bind)
Nothing solved the issue.
Any ideas on how to get Zimbra to run on a mirror copy off the network ?
PS
On the network it starts, but ofcourse we can't have 2 mailservers with the same IP and hostname on our network.

[Cine]

Hello ppdeonet,

first of all can you please explain what you mean by "mirror copy" and how you created that?
Also, migrating to a mirror copy is a great waste of time, since ZeXtras Suite is made to do all the work

Have a nice day,
Cine

[ppdeonet]

Hi Cine,
Mirror copy is an exact copy of our production mail server.
As mentioned in previous messages our mailserver consists of a 2TB sata hdd with another 2TB data hdd in Raid 1 (mirror copy).
I want to add the mirror copy to a different system (without network connection) and boot, but unfortunately Zimbra
does not start.
Thanks,
Perry

[Cine]

The first thing that comes to my mind is a problem on the network configuration... What's your server's OS?

[ppdeonet]

Ubuntu Linux 8.04

[Cine]

You should delete the "/etc/udev/rules.d/70-persistent-net.rules" and reboot the server.
This file contains informations about the old server's network interface's MAC addres, a new and correct one will be generated at boot...

Have a nice day,
Cine