Question on btrfs

I have disk partitioning as shown in the attached image. It seems that /, /home, and /usr/local share the same partition although I allocated separated space for them during the installation. Then how can /home and /usr/local be intact when doing a reinstallation?

You need to understand how btrfs works. One btrfs volume can contain many subvolumes, such as you note for /, /home, and /usr/local. These subvolumes are somewhat analogous to partitions or LVs in an LVM system.

I have never tried a reinstall on a btrfs system, but personally would suggest a backup of the portions you want to save prior to doing a reinstall. Backups are always a good thing regardless of the file system in use.

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Yes, they are btrfs subvolumes. They are sharing a partition.

How? Did you apply quotas? Generally subvolumes share the space in the partition. That is part of their advantage, they are separate but share space.

The Blivet-GUI partitioning option allows this. You can install into an existing btrfs filesystem and select the subvolumes you want to use.

That being said, it has a been a while since I used it so you might want to test that.

I see. Thank you very much! A new installation is usually required after a new release of Fedora. I did do a backup of my data.

Thank you very much for your help. I did the same partitioning as for the ext4 file system. When adding partitions, there are options of /, /home, /var, etc, in the pulldown selections of partition names. I applied the quotas after adding the partitions. Of course, /, /home, and /usr/local share the same volume.
I just want /home and /usr/local to be intact during a new installation. Is Blivet-GUI used in the installation of Fedora?

Yes. On the partitioning screen in the installer it is one of the options

OK. I’ll try it. Thank you for your help.

You can watch this video to learn the basics of btrfs. Quite nice and easy explanation!!

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OK. Thank you very much!