Dear Maintainer, this is a feature request.

Debian related distros like POP!_os and ElementaryOS, when the system is
installed in one partition: I mean inside "/", have the ability to recognize
the previous installation and reinstalling the system without erasing the user
folders already existing, so you can reuse your actual existent user. It would
be a nice feature having the same on Debian; for desktop installations this
eliminates the necessity to have partitions separated while you can reinstall
your system several times for whatever reason. Even macOS has this feature
since a very long time.

Best regards,

Daniel

Hi,

Daniel <daniel01@mailbox.org> wrote:

The debian-installer supports similar use case via the "separate partition for
/home" approach.


Holger

Dear All,

In this case I suggest hence to expand the use cases and to evaluate the
feature to reinstall Debian on top of itself without overwriting the
home partition. While it doesn't seem a complicated achievement, it
brings instead a great advantage for the end user and improves greatly
the desktop experience, for new users as well for the power users.

My regards,

Daniel

Yes, that is what Holger is telling.


Groeten
Geert Stappers

Geert Stappers <stappers@stappers.nl> writes:

I think Daniel is requesting an option that does something like this:

  find /install-target -maxdepth 1 | grep -v 'home\|lost+found' | xargs rm -rf

Maybe this way isn't robust enough, but active mounts shouldn't have
their mount points removed, because

  rm: cannot remove '/install-target/foo': Device or resource busy

BTW, Daniel, you can decruft your system with "apt purge --autoremove
foo", which also deletes config in /etc and will notify you if any files
remain in /var.  One of the greatest strengths of Debian is that unlike
other operating systems, smooth upgrades between stable versions are
taken seriously...gravely seriously...so one never needs to reinstall.
The only things that I've seen that have ever required action are
packages that needed manual configuration updates in /etc (equally
solvable by apt purge), and obsolete/broken configuration in /home/user
(not solved if this feature request is implemented).  What problem is
this feature request intended to solve?  FrankenDebian?

https://wiki.debian.org/DontBreakDebian


Cheers,
Nicholas

P.S. apt install installation-birthday  :-)

I am addressing another case, the one you have not separated partitions
for /, /home and swap.

As a matter of fact if the installer is able to recognize the home
folder having  /home separated in another partition is not necessary
anymore. The advantage respect having the /home separated, specifically
for a desktop use are noteworthy.

If the installer, instead of creating /, /home and swap, creates just /
and a swap file and if is able to reinstall itself without overwriting
the home folder I think is a huge improvement. As a matter of fact if
you reinstall Debian, even with /home in another partition, there is not
any assisted aid that explain you how to properly setup the /home
partition. Having the system partitioned is already a setup for advanced
user.

Thanks,

D.

Hi Nicholas,

thanks for your reply, I really appreciated your constructive approach.

I use Debian since 2007 and I did a lot of installation, I personally
use a FrankenDebian (testing with pinning toward SID and Experimental)
however when I install Debian on other machines I install definitely the
current stable available. I have been performing exclusively desktop
installations and while I consider the best option separating /home
recently I found myself not able to get the right balance between "/",
"/home" and "swap". The default "/" assigned is often too small while
sometimes I wasted gigabyte never used. The "swap" with the amount of
ram available today is always more accessory and with the SSD disk the
trend is to reduce its use the most. Eventually I stopped to create a
"swap" partition in favor of a "swap-file" (like Raspian e.g.); hence I
also stopped to create "/" and "/home" but just "/" and still as LVM; at
this point you don't have anymore issue with the space and if you need
you can add all the disks you want because it is still a LVM partition.

Now the case I am figuring out is the one you didn't separe "/" and
"/home" (however the installer is still creating "swap") but you need to
reinstall Debian because you screwed it up for some reason. Now a smart
installer before to start everything takes its time to check the disk
and discovers that you have, along a crypted disk and a LVM group, also
a previous version of Debian hence check the users and it asks you if
you want keep all the users, just one, etc... and then it reinstalls the
system and recovers the setting from the user(s) you selected, without
creating a FrankenDebian but just a fresh and **smart** installation.

This leads in my opinion in creating a further voice for the Debian
install: **the desktop installation**; Standard and Advanced are
eventually too generic and do not target properly the desktop cases. If
the D-I was properly able to read LUKS and LVM during the installation
time, and if was also able to perform a smart installation as described
in the paragraph above, a Desktop installation should be:

1. Create an encrypted partition by default (LUKS + LVM);

2. install everything in / ;

3. not create a "swap partition" but a swap-file.

I also add that:

4. should deactivate root user by default, which is now considering a
best practice;

5. should deactivate the source repos and asking to activate the
"contrib" and "non-free" repos (like in Advanced Mode).


I don't see any complicated tasks to achieve, others Linux distro
already started to move in this direction while other *nix operative
systems already do that since a long time.

The only issues I see here are the resistance to the changes and the
fact that actually the D-I has some issue to recognize the encrypted
partitions and if you want reinstall Debian you can't preserve any of
the partitions you want because it will consider the encrypted disks as
blanks.


Best regards,

Daniel

I rarely do that, but I can see why some people want it.

I do tend to prefer that for most setups myself.

My understanding is that suspend to disk works much easier with a swap
partition still, but my information could be out of date on that.
And of course swap smaller than ram makes suspend to disk not possible.

Not sure I agree it is considered best practices.  A lot of distributions
do it, but not all.  I do prefer root login to work from the console if
I have to fix something.

Other distributions (Certainly the case for redhat based stuff in the
past) had to do it since they didn't have a working in place upgrade.
That rather makes it required that the installer can do an upgrade and
detect existing settings.  Debian seems to have always aimed for an in
place upgrade that worked, so the installer really only had the purpose
of the initial install.  It's one of the things that made me switch to
Debian over 20 years ago.  I have never had to do a reinstall of a Debian
system except on a machine that lost the disk and I didn't have a backup
of it (nothing important was kept on that system).  I really should
have replaced that other disk in the RAID1 within a reasonable amount
of time. :)

Collecting all those settings does not sound like a trivial job, and based
on the normal use case of a Debian install, I sure don't see the value
in it.  How do you even decide which settings should be preserved and
which should not?  What if one of the settings is what broke your system?
If you screw up the system, go fix it.  You will learn something from it.
Blowing away the system and installing it again means you learn nothing,
waste a bunch of time, and will likely do it again in the future.  I have
certainly broken my installs over the years and had to fix it, but it has
always been possible.  Running unstable and experimental stuff at times
means it sometimes breaks for you and you get to put it back together.
Not a big deal.

Dear Lennart,

I hope that when one opens a "whishlist bug" at least there is a chance
to have a confrontation.

The main point I want to address is when you do a "smart installation"
it is supposed to perform a clean installation hence the only folder
that must to be untouched is "/home". The same concept when you have "/"
and "/home" in separated partitions and you perform a clean
installation. I think that is pretty trivial, the smart parts are:

* the installer is able to check for a previous Debian installation
before to begin the process;

* and in case it founds a previous installation, the installer, is able
to perform a fresh installation without overwriting the "/home" folder.

I can confirm that ElementaryOS and POP!_OS, that share the same
installer, can do that.


Last point I want touch is about the swap partition. With the SSD and
the OS able to boot in a bunch of seconds the hibernation doesn't make
any sense today. For example I have 16GB of ram, based on the standard
rules I should use at least 1.5x of the ram if not the double. It means
that I should use 32GB just to hibernate my session, no way... With the
SSD disks the lesser you write on the disk the better, I put just 2GB of
swap-file and "swappiness" at 1 and the swap is never used and I didn't
waste 30GB of space.

To conclude I think I elaborated everything clearly, I see a lot of
benefits and improvement with the suggestions I gave to Debian, I also
think that are pretty trivial to implement. I don't want introduce a
Windows behavior of "reinstall when it broken", but back to time when I
hadn't a fast internet connection it was faster download the full ISO
and performing a fresh installation rather than doing a "dist-upgrade".

The bottom line is with a smart installer you don't need to separate
your disk(s) in partitions but you can throw everything in "/" including
the "swap" as swap-file that you can modify freely based on your needs
(if you can't live without hibernation[1]). There is also a dynamic swap
manager available on Debian as well: https://github.com/Tookmund/Swapspace


My best,

Daniel

[1] It needs some tuning to work:
https://wiki.archlinux.org/index.php/Power_management/Suspend_and_hibernate#Hibernation_into_swap_file

Well I believe you have the option to not format a mountpoint during
the install already, so at least that part should be pretty easy.

Well hopefully someone will try to contribute that then.  I suspect the
main thing is finding someone that wants to implement it and do the work
to add it and maintain it.

Only advantage to huibernation is not having to close all the things
you are working on and opening them again after the next boot.  I do
find hibernation takes too long with a lot of ram and hence never do it
myself. :)

I remember upgrades over dial up.  Still did not make me want to go
download full iso images elsewhere.  It could do it while I slept.
Things have gotten a lot bigger since then though.  I have seen people
keep a subset mirror of Debian on a USB drive that they would update with
rsync once in a while at work, and bring home to use for upgrades where
the connection was slow.  Still in place upgrades of course, not using
the installer.

Hi Daniel and everyone reading this,

Daniel <daniel01@mailbox.org> writes:

Len and Daniel, WRT swap, hibernation is useful when you need to
preserve the state of applications that aren't aware of a desktop
session manager, eg: half-finished work in a terminal.  As I see it the
primary advantage to a swap file is the ability to expand it after a RAM
upgrade. eg: that a reboot using a livecd to resize partitions is not
required.  Granted, expanding a swap file is only necessary if one cares
about hibernation...

The key point is "is able to recognize [safely and reliably]", and that
requires someone who values the feature to work on debian-installer
(not fun), and also maintain it (not fun).
time to learn how to fix things if one is going to track
testing/sid/experimental than hitting the panic button and losing state.
My mother (who lives 3500km away, runs Debian stable, and installed it
herself eight years ago) doesn't need this feature.  She's not an
intermediate or advanced user and is currently running buster.  She also
has root on her laptop, so has the power to render it unusable.

Daniel, would you please take a look at Bug #941627 (ITP: grub-btrfs --
provides grub entries for btrfs snapshots (boot environments/restore
points)?  I think that this is a feature that would solve the situation
where one ran a testing/sid/experimental upgrade at a time when one
didn't have time to do the work required to fix the brokenness.

Here's how it will work:

1. Install to btrfs (after my MR is merged this will automatically
create @rootfs subvolume, eg: special directory kind of like a pseudo
logical volume).  Reboot.
2. Run a one-line command and add one line to fstab to create a @home
subvolume--this is necessary to exclude /home from the snapshots.  I can
write a beginner friendly helper script if necessary.
3. Take a snapshot before running a dangerous upgrade (easy one-line
command).  Eventually this may be automatic (eg: something like
apt-btrfs-snapshot)
4. If the upgrade produces a broken state the user doesn't have time to
fix, simply boot into a known-good copy of / using the grub menu to
select the correct entry.  If the top-most one isn't good, reboot and
try with the second top-most one until a good one is found.  After
confirming all is well, rename the @rootfs subvolume and create a new
read-write snapshot named @rootfs based on the current boot environment.
This step is only necessary if you want to reboot into the old copy of
the rootfs automatically.  You also get to keep the
@rootfs-does-not-work copy.
5. The logical progression of this feature is to create a snapshot,
dist-upgrade the snapshot, test it (without rebooting), and if
everything looks good then mark it as the default boot environment.

Eventually there will be a GUI!

While wiping and reinstalling may be the best other OSs can aspire to,
Debian can, and will, do better.  I hope you'll agree the project I'm
working on will solve the root issue you're reporting, and that you'll
agree it's a more elegant and time-efficient solution :-)

In the meantime, to remove everything but /home and reinstall without
reformatting you can reboot into a Debian rescue system or using the
Debian Live image, mount your volume, use the solution I provided in my
initial reply (p.s. I consider that a risky approach), then follow:

https://www.debian.org/releases/buster/amd64/apds03.en.html
https://wiki.debian.org/Debootstrap


Sorry for the belated reply, I've been swamped with work.
Cheers,
Nicholas