[Solved] btrfs subvolume target installation

[bester69]

Hi,
How can i install debian filesystem over a subvolume btrfs with debian's CD installation?

I tried to mount subvolume in /target directory as i usaully do with sparky distro (debian based on), but the wizard installation automatic unmount the subvolume just before to proceed with the files copy installation..and it copies all files in the / (main subvolume).

I wanted something like that:

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mount -t btrfs -o subvolid=xxx /dev/sda1 /target

so, the installation process, use the subvolume xxx for installation.


thanks.

[bester69]

I had to apply some tweaks, to get my goal:


I had previouslly created two btrfs subvolumes:
/home
/rootsys (Here, i wanted to put inside debian target installation)

0-I installed all together (the file system next to subvolumes) in the same parent level.

1- After syste, installation, I created a volume snaphot to put into it that installation:
cd /target
or
mount -t btrfs -o subvolid=0 /dev/sda1 /mnt

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btrfs subvolume delete /rootsys
btrfs subvolume snapshot ./ /rootsys

2- Clean/delete root installation outside subvolumes:

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mv /home .home
mv /rootsys .rootsys
rm -rf / (delete installation files outside snapshot rootsys)
mv .home /home
mv .rootsys /rootsys

3- Install Grub pointing to subvolume system (rootsys):

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mount --bind /dev /rootsys/dev
mount --bind /dev/pts /rootsys/dev/pts
mount --bind /proc /rootsys/proc
mount --bind /sys /rootsys/sys
chroot /rootsys
grub-install /dev/sda
update-grub

4- Editing fstab pointing to home subvolume:
btrfs subvolume list / (get ID subvolume home (649) for using in fstab)

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UUID=5a261bc5-1828-4588-b9a7-beb5f78a20e5	/	btrfs	defaults	0	1
UUID=5a261bc5-1828-4588-b9a7-beb5f78a20e5	/home/user/ btrfs subvolid=649  0 0

[pylkko]

Were you using the stable installer or does not even the RC one support btrfs install straight out-of-the-box?

[bester69]

Were you using the stable installer or does not even the RC one support btrfs install straight out-of-the-box?

I used testing netinst-distro,
Hi pylkko, thanks for ans.

It let you to pick a btrfs partition, but it doesnt let you to choose a subvolume in that partition, so i found it kind of extrange. So i came here to see if i was missleading something.

[pylkko]

maybe bug report it?

[bester69]

maybe bug report it?

I think, that's part of the wizard debian standard installation. there should be something in partition stage menu, when you choose a btrfs partition, you shoud be able to choose a subvolume.

Anyways not a big problem, now that i know i can snaphot the root installation into a subvolume.

[Head_on_a_Stick]

I don't know about the Debian installer but I have just installed Debian stretch to a btrfs formatted partiton (/dev/sda8 in this case, mutatis mutandis) in a multiboot laptop with a simple custom (flat) layout using this sequence from a "live" ISO image:

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# mkfs.btrfs /dev/sda8
# mount /dev/sda8 /mnt
# btrfs subvolume create /mnt/stretch
# btrfs subvolume create /mnt/home
# umount -R /mnt
# mount -o subvol=stretch,compress=lzo /dev/sda8 /mnt
# mount -o subvol=home,compress=lzo /dev/sda8 /mnt/home
# debootstrap stretch /mnt http://cdn-fastly.deb.debian.org/debian

Then chroot into the system and configure it as per https://www.debian.org/releases/jessie/ ... 03.html.en

Pro tip: for the system clock, use this to set UTC:

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# hwclock --systohc

This will create the /etc/adjtime template file

EDIT: be sure to set the custom mount options correctly in /etc/fstab before rebooting into the installed system; for my system it would be:

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/dev/sda8 / btrfs rw,compress=lzo,space_cache,subvol=stretch 0 0
/dev/sda8 /home btrfs rw,compress=lzo,space_cache,subvol=home 0 0

[bester69]

I don't know about the Debian installer but I have just installed Debian stretch to a btrfs formatted partiton (/dev/sda8 in this case, mutatis mutandis) in a multiboot laptop with a simple custom (flat) layout using this sequence from a "live" ISO image:

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# mkfs.btrfs /dev/sda8
# mount /dev/sda8 /mnt
# btrfs subvolume create /mnt/stretch
# btrfs subvolume create /mnt/home
# umount -R /mnt
# mount -o subvol=stretch,compress=lzo /dev/sda8 /mnt
# mount -o subvol=home,compress=lzo /dev/sda8 /mnt/home
# debootstrap stretch /mnt http://cdn-fastly.deb.debian.org/debian

Then chroot into the system and configure it as per https://www.debian.org/releases/jessie/ ... 03.html.en

Pro tip: for the system clock, use this to set UTC:

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# hwclock --systohc

This will create the /etc/adjtime template file

EDIT: be sure to set the custom mount options correctly in /etc/fstab before rebooting into the installed system; for my system it would be:

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/dev/sda8 / btrfs rw,compress=lzo,space_cache,subvol=stretch 0 0
/dev/sda8 /home btrfs rw,compress=lzo,space_cache,subvol=home 0 0

I take note of it, thanks a lot.