Docker Storage Driver

Docker provides us pluggable storage driver architecture. It gives us the flexibility to "plug in" the storage driver in our Docker. It is completely bases on the Linux filesystem.

To implement, we must set driver at the docker daemon start time. The Docker daemon can only run one storage driver and all containers created by that daemon instance use the same storage driver.

The following table contains the Docker storage driver.

TechnologyStorage driver name
OverlayFSoverlay or overlay2
AUFSaufs
Btrfsbtrfs
Device Mapperdevicemapper
VFSvfs
ZFSzfs

Current Storage Driver

To check which storage driver is used by the daemon, we can use the following command.

Docker Storage driver 1

We can see that the above command shows the storage driver used by the daemon. The Backing Filesystem is extfs. The extfs means that the overlay storage driver is operating on the top of the filesystem.

The backing filesystem refers to the filesystem that was used to create the Docker host's local storage area under /var/lib/docker directory.

The following table contains storage drivers that must match the host?s backing filesystem.

Storage driverCommonly used onDisabled on
overlayext4xfsbtrfsaufsoverlayzfseCryptfs
overlay2ext4xfsbtrfsaufsoverlayzfseCryptfs
aufsext4xfsbtrfsaufseCryptfs
btrfsbtrfsonlyN/A
devicemapperDirect-lvmN/A
vfsdebugging onlyN/A
zfszfsonlyN/A

Note:- "Disabled on" means some storage drivers can not run over certain backing filesystem.

Setting Storage Driver

We can set storage driver by setting its name to the dockerd command. The following command starts a daemon and set new driver.

Later on, we can check docker driver by the following command.


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