Provision Docker Storage on a Dedicated Block Device

Internal

• OpenShift 3.5 Installation

Procedure

Provision an unformatted block device. For this example, it will be referred to as /dev/sdb.

Create one partition that spans the entire device. Either fdisk or sfdisk can be used. This is how the partition is created with fdisk.

The procedure will create a /dev/sdb1 partition.

Erase all signatures from the partition:

wipefs -a /dev/sdb1

Initialize the partition for use by LVM by creating a physical volume:

pvcreate /dev/sdb1

Create the volume group, conventionally named "docker_vg", using the partition prepared by the previous steps /dev/sdb1:

vgcreate docker_vg /dev/sdb1

Crate the LVM thin pool:

lvcreate -y --type thin-pool --zero n -c 512K --poolmetadatasize 1041s -L 500M -n docker-pool docker_vg

Enable auto-extension (optional):

Store:

activation {
	thin_pool_autoextend_threshold=60
	thin_pool_autoextend_percent=20

}

in /etc/lvm/profile/docker_vg--docker-pool-extend.profile and then:

lvchange --metadataprofile docker_vg--docker-pool-extend  docker_vg/docker-pool

Verify that the LV is correctly created:

#lvs

  LV          VG        Attr       LSize   Pool Origin Data%  Meta%  Move Log Cpy%Sync Convert
  docker-pool docker_vg twi-a-t--- 500.00m             0.00   0.88
  root        main_vg   -wi-ao----   7.00g

Write /etc/sysconfig/docker-storage:

DOCKER_STORAGE_OPTIONS="--storage-driver devicemapper --storage-opt dm.fs=xfs --storage-opt dm.thinpooldev=/dev/mapper/docker_vg-docker--pool --storage-opt dm.use_deferred_removal=true"