Help with Ubuntu 18.04.5 to 20.04.1 Upgrade

Is there a guide for upgrading a Virtualmin Pro 18.04.5 system to Ubuntu 20.04.1?

I did not find a guide in the documentation the last ones are ancient dealing with 14.04 to 16.04.

Thank you

This is more a general question about upgrading an operating system and how safe - or unsafe - it is to do it. So in theory you could leave “Virtualmin” out of that sentence.

If you search the forum for upgrade ubuntu you will find quite a few hits of other people who have attempted it, and their successes and failures.

I have done it before - and it was a simple Virtualmin installation and all went swimmingly. Also because Virtualmin just “wraps” around the OS, in theory at least, Virtualmin should keep on running.

So in my case, I simply did what the operating system told me namely:

New release '20.04.2 LTS' available. Run 'do-release-upgrade' to upgrade to it.

DISCLAIMER: Having said that, a lot could depend on your system. Upgrading a more complex or customized operating environment is not always guaranteed to go smooth. I would only attempt to do this if you had fairly advanced system admin skills and / or you are willing to google to fix possible issues. Of course the guys on the forum could possibly volunteer their advice too.

In an ideal situation, you would snapshot your server, do the upgrade, and be ready for roll-back.

But in my opinion, if you love sysadmin and at least have some skill, by all means, upgrade.

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Yes thanks for the note. THere are many articles about upgrading Ubuntu most are ancient and deal with the very problematic 14.04 pre systemd systems to more recent versions. I still have domains marooned on an older version of Ubuntu running virtualmin as they will not restore correctly into a 18.04 system without breaking the server entirely and having to resort to a full restore.

It would be good to see updated documentation with the ‘gotchas’ and there will be some documented. I would image there will be a lot of clients needing to upgrade to 20.04 as this brings Postfix SNI capability at last to these shared IP virtual hosting platforms. One of the major reasons for upgrading for us. Only the Virtualmin team know what they have changed within the scripts to deal with the later versions. I am a Pro customer and love Vmin and Webmin. But not keen to spend days trying to find an esoteric issue following a supposedly good upgrade.


There are no guides because none are needed. You’re upgrading the OS, not Virtualmin. I went from 18.04 to 20.04 from the Ubuntu console. Rebooted after the update finished and everything was just fine.

Maybe you were the lucky one! I will continue to look for detailed guidance from others who have upgraded a Ubuntu 18.04 Virtualmin system with many virtual servers to a Ubuntu 20.04 system.


Good luck with that since one has nothing to do with the other.

Be very careful (make backups, in other words)! I recently helped a customer who had attempted exactly this and ended up with a non-working server for more than a day as a result. I found and fixed half a dozen serious problems in order to get it all working again. Things like removing and recreating all SQL users, uninstalling and reinstalling apt packages, disabling and re-enabling SSL mode on all sites.

I did some experiments (using virual machines) to see when it does and doesn’t work. I found that I could run “do-release-upgrade” on a clean Ubuntu 18.04 installation before any sites were added and convert it to Ubuntu 20.04 quite successfully. I could also usually backup individual Virtualmin sites from 18.04 and restore them to 20.04 quite successfully (though not always - Drupal 7 sites wouldn’t restore, for example). Backing up a Webmin configuration from 18.04 and restoring it to 20.04 did NOT work, however.

So on the whole I would recommend that you do NOT run do-release-upgrade on a live server unless you can tolerate some considerable downtime. Running it on a new server and then copying sites across might work but then your IP address will change and you’ll have to change all your DNS records.

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@philmck many thanks for the response. That was my fear. Having used Vmin for 8 years or so it is not without its issues when moving from platform to platform. I currently have some marooned virtual servers on a previous older version of Ubuntu that I cannot get to restore even on my 18.04 server and can’t get the downtime agreed to do them manually so they are stuck for the moment.

Thanks for the advice. Yes I always take a snapshot before any updates to the server, even normal Ubuntu updates JIC I have to roll back. Downtime is usually only a few minutes for the restore and reboot.

I have had very mixed success with the backup and restore functionality.


For customers who can’t tolerate downtime, I’ve managed to migrate them in the past by first copying a snapshot of the site to the new server, and taking my time to fix all the problems. Then when it’s time to switch, I set up an rsync job (via SSH) to sync all files including emails (one way). I take the site offline briefly at 3am to copy the database contents to the new server and set the old server to connect to that (which may require firewall modification). Then if all is good I bring both sites up, change the DNS and wait 24 hours for everything to propagate. During this time emails could arrive at either server but rsync keeps them in sync. Not quite zero downtime but pretty close.