There are two ways to upgrade to Zimbra OSE 9. The first, which is the simplest and fastest, is to update Zimbra 8.8.15 OSE on the server to a new version. This approach has exactly two drawbacks. The first is that you will need a sufficiently long technical break to implement 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 upgrade to Zimbra OSE 9 is to migrate from a server based on Zimbra OSE 8.8.15 to a server with Zimbra OSE 9. This approach is a little more complicated to implement, but it does not require a long technical break, and in case of problems on one server , you will always have another server at hand with a fully functional Zimbra OSE.
In order to update, you need to download the Zimbra 9 distribution from the Zextras website and run the installer, which will independently detect the installed Zimbra OSE 8.8.15 and offer to update the mail server to the new version. The update process is similar to the installation process for Zimbra OSE 9, which is detailed in our previous article.
We will consider the migration process using the example of the company.ru domain. Zimbra OSE 8.8.15 runs at mail.company.ru, and Zimbra OSE 9 will be installed at zimbra9.company.ru. In this case, the MX record in DNS points exactly to the mail.company.ru node. Our task will be to transfer the accounts of the company’s employees from the mail system at the mail.company.ru node to the system deployed at the zimbra9.company.ru node.
The first step towards doing this is to create a backup on one server and deploy it to another. This task is accomplished using the Zextras Backup extension included with Zextras Suite Pro. Please note that for a successful backup transfer, the same version of Zextras Suite Pro must be installed on both servers. 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 that indicated.
To perform the migration, it is recommended to use an external hard drive or network storage device mounted in the / opt / zimbra / backup / zextras / folder, where the mail server is backed up by default. This is done so that the creation of a backup does not create additional load on the running system.
Let’s start the migration by disabling the real-time scanning function on both servers using the command zxsuite backup setProperty ZxBackup_RealTimeScanner false… Then launch SmartScan on the source server 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 completing the operation, 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.
Then you can start deploying the backup to the target infrastructure. This is done using the command zxsuite backup doExternalRestore / opt / zimbra / backup / zextras /… When the deployment is complete, you will receive a healthy copy of the old server that you can bring to 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, it is necessary to make changes to the hostname and DNS record of the zimbra9.company.ru host so that users logging into the web client will get into Zimbra OSE 9.
However, the work has not yet been completed. The fact is that 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 arriving at the server with Zimbra OSE 8.8.15, you need will back it up again. Thanks to Smart Scan, only the data that was missing in the previous backup will be included in it. Therefore, the process of transferring fresh data will not take long.
The same operations can be performed in the graphical administrator console. The screenshots provided in the article show the process of creating and importing a backup.
An obvious consequence of this approach to updating the server is that Zimbra users will not have access to some of the received and sent emails for some time, but they will be able to normally receive and send emails. In addition, during direct restoration of mailbox contents, server performance and responsiveness may drop, but all these nuances are much better than a long technical break and the associated temporary unavailability of the service.
For all questions related to the Zextras Suite, you can contact the Representative of the Zextras company Ekaterina Triandafilidi by e-mail firstname.lastname@example.org