Part 1 - Reclaim /dev/sdb1

This disk were used by /wharf partition, and is now reclaimed to be dedicated to Docker images (and managed by Docker engine).

• Removed former Docker's loopback devices
• Moved data from /wharf to /home or /var
• Detached /dev/sdb1 from LVM main volume group

Part 2 - A volume group for Docker

• Created a volume group for Docker, «Schwimmsteg»
• Created two logical volumes to store Docker content:
  • /dev/schwimmsteg/docker-data
  • /dev/schwimmsteg/docker-metadata

Volume group creation

$ vgcreate schwimmsteg /dev/sdb1
Physical volume "/dev/sdb1" successfully created
Volume group "schwimmsteg" successfully created
$ lvcreate --wipesignatures y -n docker-data schwimmsteg -l 97%VG
$ lvcreate --wipesignatures y -n docker-metadata schwimmsteg -l 3%VG

Docker configuration

--storage-opt dm.datadev=/dev/schwimmsteg/docker-data --storage-opt dm.metadatadev=/dev/schwimmsteg/docker-metadata