Greetings,
I have recently installed Debian with a root disk formatted with btrfs
(RAID 10 with 4 drives of 12TB each.)
root@zeus:~# uname -a
Linux zeus 5.4.0-3-amd64 #1 SMP Debian 5.4.13-1 (2020-01-19) x86_64 GNU/Linux
root@zeus:~# btrfs --version
btrfs-progs v5.4.1
root@zeus:~# btrfs fi show
Label: 'root' uuid: bfd97357-7f10-4648-88a4-6521c6c4bb9c
Total devices 4 FS bytes used 775.79GiB
devid 1 size 10.00TiB used 388.53GiB path /dev/sda2
devid 2 size 10.00TiB used 388.53GiB path /dev/sdb2
devid 3 size 10.00TiB used 388.53GiB path /dev/sdc2
devid 4 size 10.00TiB used 388.53GiB path /dev/sdd2
root@zeus:~# btrfs fi df /
Data, RAID10: total=776.00GiB, used=774.84GiB
System, RAID10: total=64.00MiB, used=112.00KiB
Metadata, RAID10: total=1.00GiB, used=966.09MiB
GlobalReserve, single: total=512.00MiB, used=0.00B
root@zeus:~# dmesg > /tmp/dmesg.log
I've run out of space:
root@zeus:~# df -h
Filesystem Size Used Avail Use% Mounted on
udev 16G 0 16G 0% /dev
tmpfs 3.2G 9.2M 3.2G 1% /run
/dev/sda2 20T 777G 0 100% /
tmpfs 16G 0 16G 0% /dev/shm
tmpfs 5.0M 4.0K 5.0M 1% /run/lock
tmpfs 16G 0 16G 0% /sys/fs/cgroup
tmpfs 3.2G 16K 3.2G 1% /run/user/1000
root@zeus:~#
and I've tried balancing (both data and metadata) to get both the
system and btrfs to agree on how much free space I have.
I've also tried resizing the disks smaller and then larger - I found a
(perhaps misleading) post on an online forum suggesting such things to
retrieve space.
I have no idea how to proceed to fix things.
If you'd like to see the dmesg output, please let me know - it didn't
look very informative.
Any help, pointers, or suggestions is very welcome.
Thanks you for your time!
-m
