After Zextras own builds of Zimbra Collaboration Open-Source Edition 9, many administrators decided to upgrade their mail servers to the new version and turned to Zextras technical support with a question about how this could be done without compromising the performance of one of the enterprise's key systems.
There are two ways to upgrade to Zimbra OSE 9 from Zextras. The first, which is also the easiest and fastest, is updating Zimbra 8.8.15 OSE on the server to a new version. There are exactly two downsides to this approach. The first is that you will need a long enough technical break to carry out the update, the second is that if something goes wrong, you risk being left without a working system and can spend a lot of time getting it to start functioning again. The second way to migrate to Zimbra OSE 9 is to migrate from a Zimbra OSE 8.8.15 based server to a Zimbra OSE 9 based server. , you will always have another server at hand with a fully functional Zimbra OSE.
In order to upgrade, you need to download the Zimbra 9 OSE distribution from the Zextras website and run the installer, which will automatically detect the installed Zimbra OSE 8.8.15 and offer to upgrade the mail server to the new version. The upgrade process is similar to the Zimbra OSE 9 installation process, which is detailed .
We will consider the migration process using the company.ru domain as an example. Zimbra OSE 8.8.15 runs on the mail.company.ru host, while Zimbra OSE 9 will be installed on the zimbra9.company.ru host. At the same time, the MX-record in DNS points exactly to the mail.company.ru node. Our task will be to transfer the accounts of employees of the enterprise from the mail system on the mail.company.ru node to the system deployed on the zimbra9.company.ru node.
The first step towards its implementation is to create a backup on one server and deploy it to another. This task is performed using the Zextras Backup extension, which is part of the Zextras Suite Pro. Please note that for a successful backup transfer, both servers must have the same version of Zextras Suite Pro installed. We also draw your attention to the fact that the minimum version compatible with Zimbra OSE 9 is Zextras Suite Pro 3.1, so you should not try to transfer data with a version lower than indicated.
To perform the migration, it is recommended to use an external hard drive or a network storage device mounted to the /opt/zimbra/backup/zextras/ folder, where the mail server backup is saved by default. This is done so that creating a backup does not create an additional load on a running system.
Let's start the migration by disabling the real-time scanning feature on both servers using the command zxsuite backup setProperty ZxBackup_RealTimeScanner false. Then, on the source server, run SmartScan using the command zxsuite backup doSmartScan. Thanks to this, all our data is exported to the /opt/zimbra/backup/zextras/ folder, that is, it will be on external media. After the operation is completed, mount the media on the target server. Also, if the speed of the internal network allows, you can use the rsync utility to transfer the backup.
After that, you can start deploying the backup on the target infrastructure. This is done using the command zxsuite backup doExternalRestore /opt/zimbra/backup/zextras/. At the end of the deployment, you will have a working copy of the old server that you can put into production. to do this, you need to immediately make changes to the MX record of the DNS server and switch the flow of letters to the target infrastructure. In addition, you need to make changes to the host name and DNS record of the zimbra9.company.ru host so that when users enter the web client, they get into Zimbra OSE 9.
However, the work is not yet completed. The fact is that the letters that came after the end of the backup and before switching the flow of letters to the new server are still stored in Zimbra OSE 8.8.15, so immediately after the letters stop coming to the server with Zimbra OSE 8.8.15, you need will back it up again. Thanks to Smart Scan, only the data that was not in the previous backup will get into it. Therefore, the process of transferring fresh data will not last long.
The same operations can be performed in the graphical administrator console. The screenshots given in the article sequentially show the process of creating and importing a backup.
The obvious consequence of this approach to updating the server is that Zimbra users will not have access to some received and sent emails for some time, but they will still be able to receive and send email normally. In addition, during the direct restoration of the contents of the mailbox, server performance and responsiveness may drop, but all these nuances are much better than a long technical break and the temporary unavailability of the service associated with it.
For all questions related to Zextras Suite, you can contact the Representative of Zextras Ekaterina Triandafilidi by e-mail [email protected]
Source: habr.com