@mahescho All data migrations have the ability to go wrong - which is why you should try and use a new VM to test this on before you switch to the new server. If you are using VM's, then snapshots are your friend and can save having to rebuild from scratch again if the migration goes wrong. The most important but is also backup first, then take another backup (your can never have too many backups) then TEST, TEST, TEST until everything os working correctly.
Every time Grommunio release a new Appliance ISO, I do not try and upgrade my existing VM/Server, but build new from scratch, then use the plan I detailed earlier in this thread, and 'test' that is working OK before switching over to the new server. The upgrade approach (recipe) that @WalterH usually provides as soon as the new version drops usually works well. In cases wear the Grommunio server has many 10's of mailboxes, or has had a lot of customisation done to it, this is usually a good approach as if it goes OK will likely only require a couple or reboots and the server will have been fully upgraded. I just like to start from scratch (I have the time to do so) and it keeps my installation in my head in case anything goes wrong months or years down the line and I have to rebuild the server again.
The migration plan does not require you to configure anything on the new server. Grommunio generally holds all the important configuration within the sqllite databases that the plan above will copy to your new VM/server. This means that if your current server is using IMAP then the new server (after the migration) will be configured exactly the same way. HOWEVER, if you have made modifications to individual config files, then you will need to add your specific configuration changes to the new server yourself (you have these well documented of course). So the build process is:-
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- Create new VM
- From the VM console login to the Grommunio server and work down the menu items up to and including Setup wizard.
- Once the Setup wizard completes, SSH to the server and run the migration plan detailed above.
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As I mentioned in my post (3 days ago from this one) you could use the time between now and when the new version arrives (that should be based on OpenSuSe 16) to get familiar with the migration process. Also as @Andy has mentioned the new version will likely come with some bugs that will take the developers a few days/weeks to iron out once it hits the streets and user feedback comes in.
The current version based off the April 2025 Appliance ISO is pretty stable now, especially if you are only running core. So migrating to the current appliance will bring you up to date and give you the opportunity to test the migration process prior to the OpenSuSe 16 based version being released and the initial bugs resolved.
Based on you mailbox sizes you mention above, the migration of your data should take just a few minutes and your new VM/server will be ready to use.
I have about 10GB of mail (including a lot of logs files so have many thousands of small emails within that space) in 3 accounts on my server and suspect that even with my Grommunio Server being setup to use files as well I could build a new VM for Grommunio, configure and migrate all the data and have the server running in about 1 hr. (on a 3 node HP Thin Client Proxmox cluster - ie not high performance kit). I am fortunate that my spam filtering and archive are using a different product (on a separate VM) and sit internet side of my Grommunio server. This server also allows me to deliver new incoming email to both my current and any new Grommunio server I build so I can test the new server is good (with new email being delivered to it) and make it live without having to re-copy the data over again.
If the migration process fails (it did once on me early on in my Grommunio journey) you can always fall back on the PST migration method mentioned by @Andy, but that will require to setup everything again within the AdminGUI (Org, Domain, Users etc).
Hope this helps you get your server upgraded.
