USB mountpoints jumping around

[Jeffrey Walton]

On Tue, Dec 13, 2022 at 9:46 AM Ralf Mardorf via ubuntu-users
<ubuntu-users at lists.ubuntu.com> wrote:
>
> On Tue, 2022-12-13 at 13:52 +0000, Sorin Srbu via ubuntu-users wrote:
> > > Just one hint, making a backup of a running system on a file
> > > system that doesn't support snapshots, can easily result in a broken
> > > backup. So if the install and/or data is on a file system that doesn't
> > > support snapshots, better shutdown the install and run the backup from
> > > another install or a live media.
> >
> > I don't follow. Please elaborate on this when you get better!
> >
> > Veeam backup agent for linux does snapshots of running systems just fine.
>
> The first link (#Rational) explains the issue:
>
> https://en.wikipedia.org/wiki/Snapshot_(computer_storage)#Rationale
> https://en.wikipedia.org/wiki/Snapshot_(computer_storage)#Volume_managers
> https://en.wikipedia.org/wiki/Snapshot_(computer_storage)#File_systems
> https://en.wikipedia.org/wiki/Comparison_of_file_systems#Block_capabilities
>
> In Africa, people regularly pay a "prophet" 1/3 of their monthly salary
> for a bottle of gasoline juice. The gasoline juice cures cancer, brings
> dead children back to life etc., maybe programmers drink it to write
> software that can be used to take snapshots of file systems that don't
> support snapshots. However, to my limited atheist's knowledge gasoline
> can cause cancer and can kill children, I doubt that it cures cancer,
> brings dead children back to life or does other faith healing. In other
> words, is the source code of the backup software available that performs
> miracles?

Lol... :)

I think backup software can do a pretty good job if it avoids certain
directories, like /proc, /dev, /sys, /mnt, /tmp, /udev and /var/lib.
Avoiding the directories with run state mostly leaves configuration
and home directories. Maybe Veeam is sidestepping a lot of problems
using that strategy.

It would be interesting to learn if Veeam properly handled, say, a
MySQL database. MySQL usually needs something like a separate
mysqldump command.

Jeff