12 terabytes should be enough for anyone

You’d think 12 terabytes of storage would be enough for anyone.

Apparently not. My backup volume filled up last week:

# df /backup
/dev/sdg1 btrfs 12T 12T 0 100% /backup

So I bought a new eight-bay drive enclosure and eight 3TB hard drives. I just set them up and plugged into the computer. A few magic incantations with Parted and BTRFS, and now I have 24 terabytes ready to rock:

# df /backup
/dev/sdk1 btrfs 24T 0 24T 0% /backup

Next step: copying data from the old (full) array to the new (empty) one. Hoo boy– this might take a while.