[Samba] Microsoft Hyper-V over SMB 3.0

[David Disseldorp]

On Fri, 7 Jun 2013 12:24:29 +0800
Chunbo Song <massfish at gmail.com> wrote:

> We have a project about Microsoft Hyper-V by using our storage.  We want to
> use Samba to share our storage to Hyper-V.
> 
> 
> 
> And we know from Microsoft homepage hyper-v(windows 2012) only support
> smb3.0 protocol, but right now the newest version of Samba don’t’ fully
> support SMB3.0 protocol. I tried the version of  Samba4.0.6, Samba3.6.9,
> but both failed to create virtual hosts using Hyper-V.
> 
> 
> 
> So,is it possibly to use Samba to share our storage to Hyper-V?  Any
> suggestion for us?

What error are you seeing?

I did a quick test on my local Samba 4.0 + Hyper-V 2012 setup and see
an access denied error, which appears to be due the following ACL issue:

- Hyper-V connects using the machine account (machine$)
- Hyper-V connects using the login account (admin)
- admin creates VM container directory (vmdir)
- admin sets security descriptor on vmdir:
	owner=admin
	group=domain admins
	acl[0]: machine$(inherit only)=0x001f01ff
	acl[1]: machine$=0x0012008f
	acl[n]...
- machine$ attempts to open a non-existing "vmdir\Virtual Machines"
  path, which fails at realpath() with EPERM. The ACL on the parent
  does not allow machine$ execute permission, so realpath() is unabled
  to traverse. This step would succeed on Windows, as the "Bypass
  traverse checking" user right is granted by default.

Cheers, David