Slightly off topic and also hypothetical. Assume the same physical setup, but what if both were Btrfs?
/dev/sda1 48.8G /dev/sda2 881.6G Let's say /dev/sda1 is mounted at /mnt/one And say /dev/sda2 is mounted at /mnt/two I'd likely use 'btrfs send/receive' to replicate the subvolumes I want to keep from "one" to "two", if there's enough room. If not then I need an intermediary "third" file system, which ideally is also btrfs, but there is an -f option for send and receive that will use a file based send stream. The send/receive method of replication includes everything, no filters. It's all or nothing. Date+time stamps, xattr, posix ownership and permissions, acls, and so on. Whether I use send/receive or rsync -a or cp -a, let's just assume I'm done with /mnt/one. All of what I care about is now on /mnt/two. Btrfs has the same limitation for resize as ext4 and XFS in that the resize only happens at the end. But there is a work around, (which also has an LVM equivalent.) umount /mnt/one btrfs device add /dev/sda1 /mnt/two That's it. It's now a two device btrfs, made from two partitions on the same drive. An abbreviated mkfs (write super blocks) and filesystem resize (grow) is implied by the device add command. (In reality you need to use '--force' because the btrfs device add command will see the ext4 superblock and fail to touch sda1. Alternatively, use wipefs on the partition first.) You can mount either /dev/sda1 or /dev/sda2 or by UUID, and Btrfs handles it. And there's no need to change /etc/fstab. There is a bit of a goofy UI/UX issue in most desktops, in which they show each device node making up this file system, rather than one file system icon. That needs to be cleaned up but it's a cosmetic bug that confuses the user, it's not confusing Btrfs or data on the file system. https://gitlab.gnome.org/GNOME/gvfs/-/issues/519 -- Chris Murphy _______________________________________________ users mailing list -- users@lists.fedoraproject.org To unsubscribe send an email to users-le...@lists.fedoraproject.org Fedora Code of Conduct: https://docs.fedoraproject.org/en-US/project/code-of-conduct/ List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines List Archives: https://lists.fedoraproject.org/archives/list/users@lists.fedoraproject.org
