[Feature Request] - Complete Optical Drive support

[ned.stark]

Hi,

 

I would like that uNRAID support Optical drives 100%; currently in 6.3.0-rc1, my windows VM can see, open the optical drives but the moment any interactions are started with the files on the drive the system hangs.

 

This is a must-feature for users looking to burn movies from their collections for road-trips (i don't think anyone wants to burn through their data to watch multiple children's cartoons) or archival for backup (back-up server is still an electronic machine that can go down/fail etc.; I trust my archival blue-rays to hold contents that I can access).

 

Thanks!

[jonp]

Hi Ned and thank you for your request.  As I indicated in the other thread, this isn't going to be something easy for us to solve as its an issue in the virtualization stack itself.  There are multiple ways you can pass through these types of devices to virtual machines on unRAID.  You can pass them through as block devices (e.g. /dev/sdX), you can pass them through as SCSI devices (e.g. [7:0:0:0]), or you can pass through the entire storage controller that the device is attached to (e.g. 00:1f.2).  When passing through a storage device at the block level, the device itself is presented in the guest as an emulated device (e.g. QEMU Virtual Hard Disk).  This means that the device's capabilities are flattened down to a basic set of features.  When passing them through as a SCSI device to the Virtio-SCSI controller, the device is presented without emulation.  However, many software utilities want to be able to talk to the device in a way that requires special commands to be issued through the storage controller (in this case, our emulated VirtIO-SCSI controller) and this is where things get tricky with optical drives because these commands don't seem to work through the Virtio-SCSI controller.

 

This is why the 3rd option, passing through an entire storage controller, can be the best for getting an optical drive to be seen and to function correctly within a guest VM.  In this setting, there is no emulation in the path between the guest and the underlying optical drive, allowing for all native capabilities to function as they normally would.

 

This isn't to say we won't ever have support for this, but it is fairly low priority because...

 

1) It is possible to get an optical drive working within a VM, albeit they not as seamless and simple as we'd like.

2) This feature isn't requested very often (only a handful of folks even care for this).

3) The code required to solve the issue applies to a component within unRAID that we do not develop ourselves (part of upstream projects).

[ned.stark]

Thanks for your reply and input Jon.

 

The third option you mentioned, passing the entire storage controller, wouldn't that result in all hard drives attached to that storage control to get passed through as well? In my current setup, I have 3 hard drives (cache, 2 storage) along with the optical drive connected to the SATA ports on-board the motherboard. I have a HBA for my other hard drives that are being used by unRAID.

 

So I guess option 3 wouldn't be viable in my case?

[jonp]

Correct.  You would need to add another storage controller to the system just for the purpose of assigning to a VM. There are numerous low cost options for single / dual port SATA controllers.

[landS]

Single controller with both sata and USB 3.0    

 

https://m.newegg.com/Product/index?itemnumber=9SIA67049F2226&nm_mc=KNC-GoogleMKP-Mobile&cm_mmc=KNC-GoogleMKP-Mobile-_-pla-_-Gadgets-_-9SIA67049F2226&gclid=Cj0KEQjw4fy_BRCX7b6rq_WZgI0BEiQAl78ndzY9PQ6NhAyN4r4CfCYn4AcipsGYOOFELnMYmNTZiTsaArRw8P8HAQ&gclsrc=aw.ds

[Msan]

Single controller with both sata and USB 3.0    

 

https://m.newegg.com/Product/index?itemnumber=9SIA67049F2226&nm_mc=KNC-GoogleMKP-Mobile&cm_mmc=KNC-GoogleMKP-Mobile-_-pla-_-Gadgets-_-9SIA67049F2226&gclid=Cj0KEQjw4fy_BRCX7b6rq_WZgI0BEiQAl78ndzY9PQ6NhAyN4r4CfCYn4AcipsGYOOFELnMYmNTZiTsaArRw8P8HAQ&gclsrc=aw.ds

 

That doesnt have a SATA port.. it has a SATA power connector..

[ned.stark]

I found a "system pulled" LSI controller for 15 dollars (brand new costs 115). It is from server supply. They offer a one year warranty for an additional 20 bucks. I guess $35 for a 2xSAS to 8 X SATA is a better investment as I could potentially re-purpose it in the future for another box.