I am replacing a set of 4 x 3TB disks with 4 x 6TB disks in a server that holds backups. I did btrfs replace on one disk, and that has completed but is still showing the original size: Total devices 4 FS bytes used 5.21TiB devid 1 size 2.73TiB used 2.73TiB path /dev/sda3 devid 2 size 2.73TiB used 2.73TiB path /dev/sdb3 devid 3 size 2.73TiB used 2.73TiB path /dev/sdc3 devid 4 size 2.73TiB used 2.73TiB path /dev/sde3 /dev/sde3 replaced /dev/sdd3, and the partition itself is definitely the correct size: major minor #blocks name 8 19 2929216967 sdb3 8 67 5859472967 sde3 8 51 2929216967 sdd3 8 35 2929216967 sdc3 8 3 2929216967 sda3 I've tried running a btrfs resize but it hasn't changed anything. Google just keeps giving me the same pages telling me about how replace works and why btrfs is awesome, but nothing that will actually fix the problem so far... Does anyone know how I might fix this? Thanks James