Mount VDI as logical drive on host

Discussions related to using VirtualBox on Windows hosts.
mpack
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Re: Mount VDI as logical drive on host

Post by mpack »

johnbot wrote:it gives you a warning that "to modify this vdi file will cause the upper layer snapshot does not available!" - Whatever that means
It means: In a snapshot chain each new file stores only those sectors which it thinks have changed since the new file was created. If you go in and modify an early member of the chain then it effectively corrupts every newer file in the chain, because the newer files have no knowledge of the change you made. Also VirtualBox has a "modification UUID" record to detect if older members have been modified improperly, and you may find that it then refuses to work even if the corruption would be recoverable.

Avoid snapshots (use full clones instead) and problems like these do not arise.
Giangi
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Re: Mount VDI as logical drive on host

Post by Giangi »

It's a real shame that after so many years there isn't an official tool directly from VB itself to fully mount a VDI file on Windows hosts...
Martin
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Re: Mount VDI as logical drive on host

Post by Martin »

Giangi wrote:It's a real shame that after so many years there isn't an official tool directly from VB itself to fully mount a VDI file on Windows hosts...
The current business model of VirtualBox for new features requires a customer paying for it or volunteers contributing the code...
mpack
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Re: Mount VDI as logical drive on host

Post by mpack »

I suspect people have no idea what they're asking for. Is VirtualBox supposed to make a disk formatted (say) with a Linux ExtX filesystem somehow usable on Windows?

Third parties (e.g. PowerISO) have the basic "VDI is a virtual drive in Windows" feature quite well covered. Their answer to my previous paragraph is no: Windows can only access the drive contents if it understands the filesystem.
Giangi
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Re: Mount VDI as logical drive on host

Post by Giangi »

mpack wrote:I suspect people have no idea what they're asking for
I do know what I'm asking for... I made the good (wrong?) decision to convert some of my VHD files to VDI and now I cannot mount them on the host. I do not need to mount them all the time, but for a few tasks like retriving some big files or defragmenting the disk is much more quicker/easier to do it on the host!

Obviously the host SO must understand the virtual disk file system! But, for me, this is not a problem since my virtual disk are all NTFS!

I moved to VDI because somewhere I've read is better and more robust than VHD but I may reconverting them back to VHD to solve my problem since these are perfectly integrated on my Seven!
mpack
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Re: Mount VDI as logical drive on host

Post by mpack »

As I already mentioned, there are third party tools such as PowerISO which can mount a VDI in the host (read only). If the host OS understands the filesystem inside, then you can read the files. This simply isn't a feature provided by VirtualBox.

Or, you can start up the VM and access files you want as a network share, like people would typically do when they have two PCs.
Giangi
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Re: Mount VDI as logical drive on host

Post by Giangi »

mpack wrote:This simply isn't a feature provided by VirtualBox.
I know!!!! I have simply wrote that is a shame that is not provided... I have to had, since it wasn't clear, in write mode...

Anyway, much easier to revert back to VHD...
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