Manually adding persistent storage to a VirtualBox VM of boot2docker

0_AddingPersistentVirtualDiskToBoot2Docker.md

These instructions build on those provided here and here.

Before doing the following, create a new virtual disk and attach it to your VM. The size of the virtual disk just depends on what you intend to use/run and how many containers you intend to run. The default, 8 GB, is probably more than enough and is reasonable to use if in doubt since the default mode dynamically allocates the drive as needed.

Boot the VM and run just

fdisk -l

To see the disk device name(s) and their size. In this case it's the /dev/sda shown here that has 8 GB capacity:

Disk /dev/sda: 8589 MB, 8589934592 bytes

Run the following to setup a partition on that disk:

sudo fdisk /dev/sda

Use the n option to create a new partition, choose a p (primary) partition and go with partition number 1. Accept the defaults for the cylinder choices to fill the entire disk.

Use w to write the partition changes and exit.

If you get an error about ioctl not able to re-read, then reboot the VM:

sudo reboot

Format the filesystem on that partition being sure to assign the label boot2docker expects for the data volume:

sudo mkfs.ext4 -L boot2docker-data /dev/sda1

Reboot to allow the new disk and mount point to go into affect:

sudo reboot

To make sure it did what we expected, run

df

and confirm there is are /mnt/sda1 and /mnt/sda1/var/lib/docker mounts (but with appropriate disk and partition identifiers for your setup). If you really want to connect all the dots, do

ls -ld /var/lib/docker

1_MoreInfo.md

NOTE: don't forget to configure two virtual network devices:

• A NAT device so the boot2docker instance can get to the external repos
• A host-only device so you can ssh into the boot2docker

thanks, it is very useful for me

This is fantastic! I have been looking for this for days. Thanks for the clear explanations and walkthrough.