Vista and Windows 7 and raw disks please confirm

[javaboyuk]

Guys

(I want to run opensolaris 2009.6 as guest in a VirtualBox (2.2.4) on a windows platform so
I can do ZFS with samba shares)

ZFS only makes sense on RAW disks == (BUT it would take 240 hours to make the files on top of the
NTFS partitions 5 lots of 1.81 TB files, which have to be made serially as Virtualbox won't let you
have one being created while creating another )

I HAVE READ OTHER POSTS, but I would like someone from Virtualbox to confirm the following:

"VirtualBox 2.2.4 on Windows Vista and Windows 7 beta do not support RAW disk or partition access"

I would then make the request that the documentation for virtualbox be updated to say the above too

Many thanks
Russel

PS. The problem I have is the drive for the Sil3132r5 is only for windows and Mac osx, so
not possible to run my array natively in versions of sol or BSD which have ZFS. If anyone
knows another source for a drive for it I would be really pleased!

[frank]

Actually I never tried raw disk access on Windows Vista or on Windows 7. Why do you think that this does not work, which error message do you get when you try to create a VMDK container for a raw partition?

[McStarfighter]

@Frank Mehnert (written in German): Beginnend mit Vista und Server 2008 hat Microsoft den sogenannten "Raw Disk Access" erheblich eingeschränkt. Die derzeit einzige brauchbare Lösung ist ein spezieller Treiber von www.eldos.com, welcher aber erstens mindestens 850 $ kostet und zweitens nicht als Endnutzer-Produkt konzipiert ist; will heißen: Dieser Treiber muß von Softwareproduzenten wie eben Innotek oder VMware lizenziert und dann in die eigenen Produkte eingepflegt werden.
Dieser Raw Disk Access ist, wenn ich mich nicht irre, nur noch im Kontext des Systems anwendbar, nicht mehr im Userspace und auch nicht als Admin. Tja und ohne RDA gibt es bei KEINER Virtualisierungssoftware einen Zugriff auf physikalische Platten. Ausnahme: USB-Festplatten, wenn sie auch als solche in die VM durchgereicht werden.

Vielleicht könntest du das ja mal ins Englische dolmetschen, mir brummt grad der Schädel. Danke.

[javaboyuk]

Thanks McStarfighter, but can anyone translate that for me?

I get timeout errors when trying to access the disk "well see zpool import fail" or do a search for RAW on this site
and see loads of people having problems the RAW and vista or windows 7.

BUT then in the zpool import failed thread says it was working on VB1.5 (I think) and only fails after updgrade to
2.x VB !

[javaboyuk]

Should I raise a ticket for this then?

Is it a bug in Vista/Windows7 or VB on these platforms?

I was going to "upgrade" to Windows 7 (64bit) but will not
if it means loosing access to my 10TB of raw storage managed by
my Solaris and ZFS Virtual Machine. But I so want more than
1 CPU for the VM !!!!

[McStarfighter]

Ok, I explain it in English ...

The short way: It is an official feature of MS.
The long way: Since Vista (and so Server 2008 and all Windows systems after them) MS implemented a very strong restriction for raw disk access. Absolutely no application running under any account (even the admin acc) is able to get direct access and control to a hard disk. Only the SYSTEM is able to do this. And since a few months a very special driver from www.eldos.com. But this driver is VERY expensive (at least 850 $, depends on the mass of licenses) and it isn't build for direct using by "normal" customers. This driver has to be implemented by Sun into VirtualBox.
Somewhere in the VMware VMTN there is an explaination of a workaround to "avoid" this problem. But IMHO it isn't easy and there is a "visible" chance to kill the content on the HD.

[vuser1]

Sorry, but the explanation is not enough.
What prevents the VirtualBox service to run under SYSTEM account, so it has full access to raw disk under Win2008 server?
Currently I run VBox under Linux, but plan to switch the host to Windows Server 2008. Raw disk is what I need for my medium-load Linux server. I never tried VBox under Windows, probably my question is stupid, but I know Windows architectire well and will not by this without explanation.

Is it possible to run VBox under SYSTEM account on Win2008 host so it is able to use raw disks?

[extreme_blue]

I was able to create the .vmdk file for the raw disk by right clicking on cmd and running as Administrator.
Once I got the file created, I was still getting the access error, so I decided to run VirtualBox as Adminstrator by right clicking on it and selecting run as Administrator.
This allowed me to add the disk to my virtual machine and everything is working for me now on Windows 7.

If anyone runs multiple OS, I also run Ubuntu on another system and had a similar issue. When trying to add the disk to my Virtual machine, I got an access error. Adding the user that I was logged in as to the disk group in /etc/group worked for me there.

[mpack]

What prevents the VirtualBox service to run under SYSTEM account, so it has full access to raw disk under Win2008 server?

It's a feature of Vista and later. The only thing that can write to any disk partition is a kernel mode device driver. Ring 3 apps can't do it, regardless of their privilege level. I came across this with an embedded application of mine which tried to format an sdcard (via a USB adaptor) with a non-Windows filesystem - worked on XP, but Vista blocked write access to the drive. Apparantly this was a last minute hack (just before the Vista release) after scare stories in the media about how low level disk utilities could bypass Vista's improved security.

I gave up on this feature post Vista, but as far as I know the same applies to Win7. Also as far as I know, read access always works ok. Creating the raw VMDK should work - it's only when you try to use it that it should fail, unless you try one of the immutable/differencing schemes.

I saw someone a while back claim that whole disk write access worked on Win7, though write access to a partition failed. That makes no sense to me, so I won't believe it until I get around to trying it.

[jruetten]

I would really love to get more info on this subject. I posted something a few weeks ago and go some views but no replies.

I am running Win7 Ultimate, and virtualbox 3.2.10 with a program called Nextenta which is a file server OS using ZFS as my guest. I have a Dell 420 XPS quad core 6GB of ram and 4 hard drives. One is a 320GB that runs Win7 and the other three are Seagate 2TB drives I want to create ZFS Raid1 volume on. It is these three disks I want to access using createrawvmdk. I have tested this running 2 smaller drives in a mirrored config and it worked well so I know it can be done. I just wonder what the risks are. It doesn't seem to make sense to format the drives as NTFS and then create the vdi files on that. I am afraid someone will delete or format the drives if they try and use them. If you look at the diskmgmt it shows them as unallocated and I didn't assign a drive letter so no one can see them.

I am going to finish setting it up with the 3 TB drives and make it available using CIFS to the family tonight/tomorrow and see how it goes

Anyway, I would love to hear from others that are doing this and what their experience has been. I will post an update later this week.

[klaus]

From what I know about the subject is that Vista+ blocks raw write accesses to mounted partitions and to the full disk if any partition was mounted.

Haven't tried this in a long time, but I seem to remember that I was able to use the raw disk support on Vista, provided VirtualBox was running as administrator (to get the necessary access rights to the partition) and that Vista didn't understand the filesystems on the disk. My memory could fool me though.