Recover vbox snapshot of recovered ubuntu vmdk

[conma293]

So I have a base image for a linux vmdk I snapshotted as I went along.

Now when I was going through and deleting things to free up some disk space I accidentally deleted that original vmdk, thinking that vbox would have stored the base in its own directory, not so.

Luckily I had the original vmdk backed up so I simply put it back in the directory from whence I obliterated it and thought that would be fine... not so.

I then had a hell of a time recovering it, as the <GUID> of the snapshot didnt match, I used some script to manually apply a <GUID> to the original vmdk for which the snapshot wanted. and it booted! hoorah!

heres where it gets weird - the snapshot will operate correctly for about 20 minutes, afterwhich the guest filesystem starts to apparently become read-only and thus corrupt and unusable - cant reboot successfully, if I force it off then try to boot it gives me an error "init: error.c:219: Assertion failed in _nih_error_raise_system: errno > 0"

So my question is - surely If I have in my possession - the original vmdk and all relevant snapshot files in the vbox folder, SURELY, there is a way to recreate a functioning vbox appliance???

help?

Details -

Virtualisation = virtualbox 5
Host = Win7x64
Guest = Ubuntu x64 14.04.1 krnl=3.16.0-33 generic

[mpack]

People continue to find new and inventive disaster scenarios involving snapshots. And, the appeal this feature has for newbies continues to mystefy me.

Luckily I had the original vmdk backed up so I simply put it back in the directory from whence I obliterated it and thought that would be fine... not so.

Actually, that should have done it, had the VMDK been a proper backup. Presumably then the VMDK you deleted was not a copy, but a clone. Incidentally - you made a clone but didn't locate it inside the VM folder? Not recommended: a tidy folder layout is best if you want to avoid future confusions such as this.

I used some script to manually apply a <GUID> to the original vmdk for which the snapshot wanted. and it booted! hoorah!
heres where it gets weird - the snapshot will operate correctly for about 20 minutes, afterwhich the guest filesystem starts to apparently become read-only and thus corrupt and unusable

The first sentence voids your warranty, unless you have a certificate from the Guild of Disk Hackers. Yes, from those symptoms I'd guess you used the clone for a while before creating a first snapshot, hence the contents were no longer an exact copy of the "original". The snapshot is a difference state derived from an altered base state. Change the base state and you get a corrupted current snapshot state, and there's no telling how extensive the damage is.

Time to copy off any files you would rather not lose, and delete this VM. I would suggest avoiding snapshots in future: proper backups are not only more effective in disasters, they also don't require any storage space on your host - a shortage of which is presumably behind your decision to delete important files.