Hello everyone, new user here

 

I will soon set up my very first unraid server, and while I have a bit of practical experience thanks to bash lessons and general use of linux in class, I am still very new to this stuff so please excuse me if I make obvious mistakes.

 

Right now, I don’t have access to the actual hardware on which I will install unraid, and that means I had to rely purely on research to answer my questions : so far, I have been able to find answers to everything I needed, except a few problems concerning the creation and migration of VMs.

 

So here are my questions :

 

- I saw on the official manual by Lime-Tech that you can create the vDisk for a VM on a cache-only share to use the speed of the SSDs, but in that case, your VM is not protected by the parity drive, correct ?

 

- In the case of using the cache to store VMs, I assume that the space you have to temporarily store data is reduced, but if you have several SSDs in your cache in raid 1, are your VMs protected by this raid 1 ?(I know this is really stretching the limits of what could happen in a real-life scenario here, I’m asking purely for the sake of knowing).

 

- Would it be possible to make an SSD part of the array, then create a share that can only use this SSD and making sure no other share can use it, and then use that SSD-specific share to put your VMs ?

 

- last question : once a VM is stored on your array in a specific user share, is it possible to move the image to another share or change which drive the share can use ? For example : I have an existing Windows 10 installation, I convert it to a VM using the process described on the official manual, storing the VM on a slow share protected by the parity drive. Once this is done, I can add the SSD on which the old Win1O was to the array and set it up like I described in my third question, gaining its speed.

 

The reason why I’m describing such a convoluted process is because I only have one SSD ready at hand : the one on which my Windows 10 is installed. I want to convert this installation to a VM and keep the speed of the SSD, but I am not sure I can actually do this without having another drive that can contain my installation in the meantime.

 

Thank you for your advice, I hope I made myself clear enough, as I’m not a native english speaker and I don’t have that many occasions to practice the language.

- I saw on the official manual by Lime-Tech that you can create the vDisk for a VM on a cache-only share to use the speed of the SSDs, but in that case, your VM is not protected by the parity drive, correct ?

 

Correct. But it is possible to back the VM up to parity protected array.

 

- In the case of using the cache to store VMs, I assume that the space you have to temporarily store data is reduced, but if you have several SSDs in your cache in raid 1, are your VMs protected by this raid 1 ?(I know this is really stretching the limits of what could happen in a real-life scenario here, I’m asking purely for the sake of knowing).

 

If you are using 2 or more ssd's for cache in a cache pool and your VM's located on your cache, then yes, they will be protected.

 

- Would it be possible to make an SSD part of the array, then create a share that can only use this SSD and making sure no other share can use it, and then use that SSD-specific share to put your VMs ?

 

I think there have been people who have added an ssd to the array, but I don't think this is recommended.

 

- last question : once a VM is stored on your array in a specific user share, is it possible to move the image to another share or change which drive the share can use ? For example : I have an existing Windows 10 installation, I convert it to a VM using the process described on the official manual, storing the VM on a slow share protected by the parity drive. Once this is done, I can add the SSD on which the old Win1O was to the array and set it up like I described in my third question, gaining its speed.

 

The reason why I’m describing such a convoluted process is because I only have one SSD ready at hand : the one on which my Windows 10 is installed. I want to convert this installation to a VM and keep the speed of the SSD, but I am not sure I can actually do this without having another drive that can contain my installation in the meantime.

 

Thank you for your advice, I hope I made myself clear enough, as I’m not a native english speaker and I don’t have that many occasions to practice the language.

 

I haven't tried to move a VM yet, but I do believe it is possible to move it to a different share/drive. (Put it on a cache preferred share and then when you add a cache drive it should get moved to cache by Mover?) I think you are on the right track and I did something similar. Convert your current Windows 10 install to an image that is stored on the array. Create a VM using that image. Verify it works, though it will be very slow. Once it's working, then you can prepare the SSD and start using it as a cache drive. Make sure the VM share is moved to the cache drive and it should be good to go.

You can move the vm disk image where ever you want and then point the vm manager vdisk location there.

 

You can also make duplicates of it and run it in a "new" vm.  This is what I do to keep from having to go through the process of creating a new vm each time I need one (or screw one up.) I have a base "vanilla" fresh install image on standby, ready to be copied to a new location for a new vm.

 

I believe there are ways to do "versions" of an image, but I don't mess with those.

And the reason to use cache for VM vdisk is due to write speed. If you put the ssd in array then your write speed is limited by about half the benchmark write speed of your parity disk. You will also run into write speed issue eventually because ssd in array doesn't support TRIM.

Thanks for the quick answers guys, I have everything I need and I'll be building the server in a few days.