How to backup before a release upgrade from Ubuntu 18.04.5 LTS server?

[Rei Shinozuka]

On 9/12/21 5:18 AM, Colin Law wrote:
> On Sun, 12 Sept 2021 at 07:41, Bo Berglund <bo.berglund at gmail.com> wrote:
>> My Ubuntu server, which is hosting subversion and a few websites, needs to be
>> upgraded to 20.04.3 LTS from 18.04.5 LTS18.04.5 LTS.
>> I have found a command line tutorial on how to do this here:
>> https://www.cyberciti.biz/faq/upgrade-ubuntu-18-04-to-20-04-lts-using-command-line/
>>
>> It looks OK except for this:
>> Step 1 (important) is to make a backup, but it says NOTHING about how to do
>> that..
>>
>> I have tried to figure out how but failed, most search hits talk about setting
>> up regular backup systems for the *data*, and they assume there is a desktop
>> too. But this is a headless server accessed via SSH using PuTTY on Windows.
> I  use clonezilla for full disc or partition backups.  As said by
> others you will have to shutdown the server and boot from, for
> example, a USB stick or if you have dual boots then boot from a
> different partition to backup the Ubuntu partition.  Its big advantage
> over dd or similar is that it only backs up used sections of the
> partition which can be a huge space saving.  Also it can backup over
> the network (using ssh) so you can make a backup image on a disc on a
> different machine.
>
> Colin
>
I'll second Clonezilla--it's an amazing utility I've used for years on 
Linux, Windows, OSX.

What  I like to do in this type of situation is to backup the existing 
system, swap physical boot device with fresh HD or SSD, restore from 
clonezilla to the new device, boot to and upgrade using the new device.

That way you have a known working copy of your existing system you can 
put away, plus a backup of that system, and your upgrades and 
configuration changes are using a copy on a new device. This process can 
take a little extra time (mostly watching progress bars), but you have 
maximum flexibility to roll back anything you do.

-rei