Disk space doesn't expand past 6-ish MB

[josh1703658784]

Background

Software versions

Vagrant: 2.0.1
Plugin: 0.0.42
VirtualBox: 5.2.8 r121009

Configuration

config.persistent_storage.enabled = true
config.persistent_storage.location = "./vagrant/sourcehdd.vdi"
config.persistent_storage.size = 10*1024
config.persistent_storage.mountname = 'docker'
config.persistent_storage.filesystem = 'ext4'
config.persistent_storage.mountpoint = '/var/lib/docker'
config.persistent_storage.volgroupname = 'docker'

Other configurations tried

• config.persistent_storage.mountpoint = '/external_mount'
• config.persistent_storage.use_lvm = false
• And various mount sizes

What happens

When building Docker images the build fails with No space left on device.

To determine if it was a Docker problem, I also tried running the following:
while true; do echo foobar >> /external_mount/file; done;

In both cases I see the same errors.

The external volume seems to consistently cap out between 6 and 7 MB.

Running df -h:

root@dev-build:/external/var/lib/docker# df -h
Filesystem                                     Size  Used Avail Use% Mounted on
udev                                           2.0G     0  2.0G   0% /dev
tmpfs                                          396M  5.7M  390M   2% /run
/dev/sda1                                      9.7G  4.2G  5.5G  44% /
tmpfs                                          2.0G     0  2.0G   0% /dev/shm
tmpfs                                          5.0M     0  5.0M   0% /run/lock
tmpfs                                          2.0G     0  2.0G   0% /sys/fs/cgroup
tmpfs                                          396M     0  396M   0% /run/user/1000
/dev/mapper/docker-docker                      6.8M  6.6M     0 100% /external/var/lib/docker
...

What I expect

For the mount point to expand as needed up to the size specified in the Vagrantfile.

[josh1703658784]

Issue and workaround

After looking at other issues I saw an issue with ubuntu/xenial64, which I was using. Going to ubuntu/trusty solved the problem.

[cmrunton]

@Joshuaks Could you elaborate on the issue with xenial64 that you saw? Running into this same issue and can't/won't/don't want to downgrade to trusty.

[tfkinc]

Issue is reproducible with ubuntu/xenial64 as well as ubuntu/bionic64. ubuntu/trusty64 does indeed work but support ends April 2019.

Edit: Apparently xenial and bionic do have /dev/sdb in their base image. config.persistent_storage.diskdevice = '/dev/sdc' should force the use of a different device.

[ThomasVuillaume]

Edit: Apparently xenial and bionic do have /dev/sdb in their base image. config.persistent_storage.diskdevice = '/dev/sdc' should force the use of a different device.

You just saved my day with this one ! I was fighting with this error on Ubuntu 18 for hours ! Thanks