BTW, instead of rescue mode, you can use the initramfs to do such things
(I like to do that when I don't have a LiveUSB at hand because it lets
you manipulate *all* partitions, including /).
I.e. do something like:
- Reboot
- In Grub, edit your boot script (with `e`) to add `break=mount` to the
kernel command line.
- Use `F10` to boot with that boot script.
- You should very quickly be dropped into a fairly minimal shell,
without any password.
- None of your volumes are mounted yet. Even LVM isn't initialized yet.
- Then type something like (guaranteed 100% untested)
lvm vgchange -ay # Activate your LVM volumes.
mount /dev/mapper/localhost-root /mnt # Mount /
mount --bind /dev /mnt/dev
chroot /mnt /bin/bash
lvreduce --size -50G --resizefs /dev/mapper/localhost-home
exit
umount /mnt/dev
umount /mnt
exit
--- Stefan
