[Qemu-devel] iSCSI support for QEMU

[ronnie sahlberg]

Sorry about the missing subject line in the previous mail
Got confused when using git-send-patch :-)

regards
ronnie sahlberg

On Sun, Jun 12, 2011 at 12:47 PM, Ronnie Sahlberg
<address@hidden> wrote:
> Please find attached a patch to add built-in support for iSCSI into QEMU.
> Please review and/or apply this patch.
>
> This is the latest version of this patch and I think I have addressed all 
> previous concerns and suggestions.
>
>
> Using built-in iSCSI support has many advantages for certain use cases :
>
> * if you have very many iSCSI devices it may be impractical to expose
> all LUNs to the underlying host.
>
> * the devices become private to the guest and are not visible to the host.
> This automatically avoids polluting the page-cache on the host.
>
> * security, the devices are private to the guest, which prevents other guests 
> or the host itself from accessing the devices.
>
> * security, it allows non-root users a secure way to get private and password 
> protected access to the device by using CHAP authentication.
>
> * migration, many other virtualization systems provide built-in iscsi clients 
> like this. Also providing this as feature in QEMU may make it easier for such 
> users to migrate over to QEMU/KVM.
>
> * easier to maintain. For users with very many QEMU instances I think having 
> guest-private iscsi targets and LUNs may be easier to manage than 'huge set 
> of files in /dev/scsi/*'
>
> * easier to maintain, when copying a QEMU instance from one host to another, 
> this offers a more self-contained solution where the QEMU command line itself 
> cotnains all required storage configuration, instead of also having to 
> coordinate this move with setting up and tearing down open-iscsi logins on 
> the underlying hosts.
>
>
>
>
> The patch has been tested by installing and running several distributions 
> such as RHEL6 and Ubuntu on devices, both system disk as well as the 
> installer CDROM as being iscsi devices.
>
> This testing has also been performed by running full QEMU under valgrind.
>
> Performance is comparable to using open-iscsi devices.
>
>
>