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Whats the advantage of running/creating DSM/TCRP in a VM?

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10 hours ago, phone guy said:

Why some run on a VM?


I am running a RP on baremetal, I would like to keep testing and help, but I dont have any vm setup.


Back in the day (Jun Loader) when we did not have the RedPill loader where you can add extensions and load additional drivers, it was a lot easier to install DSM on a Virtual Machine due to the drivers. For ethernet you had to use the e1000 driver which is supported by default by DS918+ and no need to worry which ethernet chips are compatible with DS918+.


Other reason, like my self, I have an AMD 3900X CPU with 12Cores/24Threads, there is no reason to utilize all 12 cores for DSM, instead I allocate 8vCores and use the other vCores for other VMs like Windows Servers, Dockers etc...


With now days virtualization you can pass through ethernet cards, hard disks, GPUs and other PCI cards.

In terms of performance you might not notice any difference between a baremetal.


Whether you use a VM or Baremetal it's a choice and there is nothing wrong either way...

Edited by gadreel
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Thank you for the detailed explanation, that all makes sense......


One of the thing I dont understand of running a vm versus baremetal, on baremetal you have 4 drive (or 6 or 8 or whatever). Your shr or raid5 (or whatever) and drive #3 fails, you replace drive 3, it rebuilds raid and your good.... if on a vm, arent you passing a virtual amount of space to dsm? or do you dedicate and pass thru sata ports 1-4 or 1-8 or whatever?


The videos I've watched show something like giving your rp/dsm vm 4tb of virtual space, but in that scenario, you dont have any protection of the raid?


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Indeed what you are asking is correct and I do not know the answer when you pass portions of your disk space to the VM but maybe the below examples will help but I am not entirely sure if my assumptions are correct.


When you pass-through entire disks you do not pass the ports. Therefore, if a disk is on port #4 on your Mobo on the VM it will display as #1 for example.


For my Virtual DS918+ I am passing through the entire disks (not portions/ I believe the SATA protocol is virtual) but this does not mean you pass through also the SMART values... so if a drive fails you might not get a warning that it failed. The message that the drive has failed I will get it on the Hypervisor (Unraid) because I can see the actual SMART values from that level.

Regarding the RAID protection since I am passing through the entire disk not virtual portions of the disk the RAID protection is valid.


When you pass portions of a disk of course it seems that you "trick" DSM thinking that the given disks are 2 separate Hard Disks when it's not and the raid protection makes no sense when both virtual disks are from the same Hard Disk. If the physical disk fails the virtual will fail also.

But as I mentioned on the previous paragraph on the Hypervisor maybe those hard disks are already on a raid protection...

Therefore, if a drive fails, your DSM will not work but your data are protected due to the raid protection of the Hypervisor. You replace the drive on the Hypervisor the array will rebuild and the 2 virtual disks will be available again on your virtual DSM.

I hope all that makes sense...


In theory, when you pass through portions of a disk that is already in Raid (does not matter 1,5,6 etc) from the Hypervisor it makes no sense to create another raid on the DSM. In my case though which I am passing through entire disks not portions of a disk that are not already raid protected by the hypervisor it makes sense to use the Raid of the DSM.

Edited by gadreel
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That is exactly what I thought, except I assumed you could pass thru or map the actual sata ports to the dsm vm.  I was going to try and use an older i7 box setup with some kind of of either additional sata card or LSI card and use those ports specifically for a dsm vm. But it didn't make sense to me, a virtual raid would be meaningless, should you suffer a failure. Now I understand the Hypervisor is handling the raid protection.  I will have to dig and see if proxmox or whichever hypervisor passes thru the actual ports. But it sounds like the way you are doing it work's too.  Passing the entire disk1 disk2 disk# thru to the VM gives dsm the raid control and protection of those disk.


I personally have 2 ds1621+, and now I have successfully converted 2 other brand nas boxes to rp/dsm, so I am ecstatic... I wanted to explore the vm side, and still be able to test and try tcrp builds without messing with my baremetal setups, get the kinks out virtually, so when upgrade time comes for the baremetal boxes I'll be prepared.  My first baremetal conversion was nail biting.. :) NO CLUE what was happening, still don't understand everything but the 2nd box (different brand, no video output at all) went so fast and quick it was uneventful and shockingly easy.  I can't wait to start exploring with a setup....


You using unraid, any suggestions on which hypervisor to use? Proxmox seems to be the popular choice, or ESXi ?

Edited by phone guy
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On my first posts I mentioned that Virtualisation now days has advanced a lot. You can pass-through that LSI card to a VM also... I believe if you pass-through the LSI the Hard Disks connected on that LSI will appear on your virtual DSM as actual drives because you are not passing through the drives like me. Those drives will look like they are physically connected to the VM and you will be able to see the SMART values also.


I believe Proxmox is a lot easier to setup than ESXI.

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