azure: Allow selecting disk controller for the VM

[krnowak]

Not even tested yet.

• Changelog entries added in the respective changelog/ directory (user-facing change, bug fix, security fix, update)

[jepio]

Awesome, this is exactly what I was hoping for!

[krnowak]

Awesome, this is exactly what I was hoping for!

@jepio: Cool. It doesn't address the issue of setting NVMe support for our images though, but I couldn't see how it can be done - the DiskControllers stuff is not exposed in GalleryImageStorageProfile. Anyway, any hints how to test it, or were you able to see if it works?

[jepio]

Awesome, this is exactly what I was hoping for!

@jepio: Cool. It doesn't address the issue of setting NVMe support for our images though, but I couldn't see how it can be done - the DiskControllers stuff is not exposed in GalleryImageStorageProfile. Anyway, any hints how to test it, or were you able to see if it works?

This stuff is underdocumented, it's through an under specified "features" field in the gallery specification.

az sig image-definition create (...) --feature DiskControllerTypes=SCSI,NVMe

Source: https://learn.microsoft.com/en-us/azure/virtual-machines/enable-nvme-faqs#how-do-i-use-a-base-image-that-supports-nvme-and-create-a-custom-image-for-my-remote-disk-.

This should translate to this change to the gallery template:

       "properties": {
         "hyperVGeneration": "[parameters('hyperVGeneration')]",
         "architecture": "[parameters('architecture')]",
+        "features": [
+          { "name": "DiskControllerTypes", "value": "NVMe,SCSI" },
+        ],
         "identifier": {
           "offer": "Flatcar",
           "publisher": "kola",

[krnowak]

Awesome, this is exactly what I was hoping for!

@jepio: Cool. It doesn't address the issue of setting NVMe support for our images though, but I couldn't see how it can be done - the DiskControllers stuff is not exposed in GalleryImageStorageProfile. Anyway, any hints how to test it, or were you able to see if it works?

This stuff is underdocumented, it's through an under specified "features" field in the gallery specification.

az sig image-definition create (...) --feature DiskControllerTypes=SCSI,NVMe

Source: https://learn.microsoft.com/en-us/azure/virtual-machines/enable-nvme-faqs#how-do-i-use-a-base-image-that-supports-nvme-and-create-a-custom-image-for-my-remote-disk-.

This should translate to this change to the gallery template:

       "properties": {
         "hyperVGeneration": "[parameters('hyperVGeneration')]",
         "architecture": "[parameters('architecture')]",
+        "features": [
+          { "name": "DiskControllerTypes", "value": "NVMe,SCSI" },
+        ],
         "identifier": {
           "offer": "Flatcar",
           "publisher": "kola",

Oh yeah, I saw the Features field, but as you said, it's undocumented and my assumption was that it was about stuff like "GPU for AI" support.

I'll update the PR.

[krnowak]

Updated, I have bumped the api version in the template too, so they match the api version used in code. I visually checked that the bump didn't require any other changes in the template.

[jepio]

@krnowak I've found the docs: https://learn.microsoft.com/en-us/azure/virtual-machines/shared-image-galleries?tabs=vmsource%2Cazure-cli#image-definitions