Today I ran out of disk space on my Macbook Air. I mean, completely out of space. I use vagrant and Virtualbox for work, and I knew that had several large, but older snapshots of virtual machines that I could remove to free up space.
And that's how today fell apart.
I also use the vagrant-vbox-snapshot plugin, and that's the tool I typically use to take snapshots when I need them.
So, looking into my project folder, I run the following:
$ vagrant snapshot list
Name: 2013-11-05 (UUID: ... )
Name: 2014-01-26 (UUID: ... )
Name: 2014-02-07 (UUID: ... )
Name: 2014-02-22 (UUID: ... )
I tend to name my snapshots after the date on which I take them. Each of these is around 8Gb in size, so I decide to delete the oldest one.
$ vagrant snapshot delete 2013-11-05
Unfortunately, whenever you remove a snapshot, VirtualBox decides to write some data to disk. Think about that for a second.
You can't remove a snapshot if your disk is full!
This command attempted to remove a snapshot, then after a minute failed with a scary message (which I forgot to copy, and have since lost). And because the VM is hosed, vagrant will offer the following complaint:
Your VM has become "inaccessible." Unfortunately, this is a critical error with VirtualBox that Vagrant can not cleanly recover from. Please open VirtualBox and clear out your inaccessible virtual machines or find a way to fix them.
And if you run vagrant status, you'll see something like this
Current machine states:
my\_vm inaccessible (virtualbox)
So, I did what Vagrant told me, and opened up VirtualBox. Well, the GUI tools listed my_vm, but also had a label next to it that said, inaccessible, and as far as I could, there were no enabled options that would let me do anything.
Needless to say, I was ready to freak out a little.
All is not lost, however. You see, there's a directoy where VirtualBox stores it's machine images and it's config data. For me, that's in ~/VirtualBox VMs/.
Inside that directory, vagrant should create a directory for each of it's vms. So, I had some data at ~/VirtualBox VMs/someproject_myvm_1234567890. The contents fo this folder look something like:
That file with the .vbox-pre is an automatically generated backup of the VirtualBox config file, prior to it saving a VM. So, here's what I did:
Replace the .vbox config with the .vbox-pre config:
cat myproject\_myvm\_1234567890.vbox-pre > myproject\_myvm\_1234567890.vbox
After that, my both VirtualBox and vagrant appeared to work with my VMs.
Crisis averted, and with only a couple hours lost.