Migrating from 20.04 -> 22.04 -> 24.04 on headless Ubuntu server + hardware upgrade

[Bo Berglund]

On Sat, 7 Dec 2024 17:46:25 -0500, Jeffrey Walton <noloader at gmail.com> wrote:

> I would back up the critical application data. You can always stand up
> a new server right now with the NUC, configure it and load the data.
> If you make a mistake, then no harm. Do it again with a modified
> process. Once the NUC is setup properly, cut it into production.
> 
Might be the safest way to install Linux from scratch....

>>
>> 2) Upgrade it to 22.04 and then to 24.04 using the do-release-upgrade command
>> Once I have the backup done as above and somehow can make it use the latest
>> kernel, then I want to do the transfer to 24.22.4 via 22.04.4
>
> One caveat that comes to mind since the machine is mission critical...
> If you migrate to 24.04, then you will have to deal with Snaps. I
> avoided 24.04 precisely due to Snap, and migrated my machines to
> Debian and Fedora instead.

Yes, I have seen a lot of snap stuff when I do df -h....

What should I choose? Probably Debian since I am used to Ubuntu server command
line?

After all this is a server version without using a desktop.
Debian is what Ubuntu is based on so I guess I could install it as a server
using the same download as with a Desktop?

Or should I install Debian *with* Desktop as a server that I never log on to?
Then I would have the future option to do some GUI stuff if need be.

But if setting it to Desktop means tons of software being installed than perhaps
not....

>> Or else - how can I make the move to new hardware?
>
>Just move the application data to a properly configured new server.

I have partitioned the existing server disk such that /home is on a separate
partition so that it won't be part of the system functions.
Likewise the Subversion data are on another partition.

So the server uses the following partition layout:

Partition       Mount point   Description
-----------------------------------------------------------
/dev/nvme0n1p1  /boot/efi     Windows/UEFI/Grub stuff....
/dev/nvme0n1p6  /             Ubuntu proper
/dev/nvme0n1p7  /var/lib/svn  Subversion data
/dev/nvme0n1p8  /home         Big partition for user data


>
>> I cannot install a fresh system on the NUC because I have no idea how to then
>> install all of the already configured services on the new hardware platform
>> fresh from start...
>>
>> I simply do not now remember what I have done over the years to
>> install/configure these since 2017 when it was originally built...
>
>Yeah, I know the feeling. I usually find my notes are incomplete, and
>have to solve some of the problems all over again.
>

What I have on this server is:
- Apache server
  Here I use LetsEncrypt certs and I do not remember how I set that up.

- Subversion plugged into Apache
  This is a backup server which receives nightly synchronization
  data from my company's Subversion server. 

- OpenVPN server with multiple services for connection to my home LAN

- Video utility that runs downloads at regular intervals using ffmpeg

When looking at the above it seems like the problem is finding the "application
data", maybe /etc should also be on a separate partition?
But I don't know how /etc works, it looks like a lot of system data I am not
knowing about is stored there as well in addition to configs for applications I
have installed...

I guess I will try to migrate by following your advice and build a fresh server,
probably using Debian.
I have to get the NUC first, though. Did not purchase one yet.

-- 
Bo Berglund
Developer in Sweden