Right way to replace/swap attached disk with another existing disk

[rickatnight11]

I'm trying to replace the root disk across a bunch of VMs by cloning the disk from a template, then swap the new disk in for the existing one. I'm having a heck of a time figuring out the right way to do this.

I have tried with DetachDisk and AttachDisk, but struggling to determine what disk ID AttachDisk is looking for (tried the UUID, but get The object or item referred to could not be found).

I have also tried a Reconfigure (similar to #790, but I don't just want to add another disk, I want to swap one in (and keep the original one "detached" in the datastore), which looks like a better option (more atomic), but I can't quite figure out the way to construct the desired change.

I basically want the equivalent of this call:

https://developer.vmware.com/apis/vsphere-automation/latest/vcenter/api/vcenter/vm/vm/hardware/disk/disk/patch/

Would love some guidance on how to approach this!

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[rickatnight11]

Digging more into the code, it looks like EditDevice is the helper function I'm looking for. Trying to figure out how to use it correctly.

[rickatnight11]

So far I've tried swapping out the disk's backing with a bare-bones one that sets a different path:

// vm = object.VirtualMachine
// newdiskpath = "[datastore-name] vm-name/new-disk.vmdk"

vmdevices, err := vm.Device(ctx)
vmrootdisk := vmdevices.FindByKey(2000)

vmrootdisk.GetVirtualDevice().Backing = &types.VirtualDiskFlatVer2BackingInfo{
    VirtualDeviceFileBackingInfo: types.VirtualDeviceFileBackingInfo{
        FileName:  newdiskpath,
        Datastore: vmrootdisk.GetVirtualDevice().Backing.(types.BaseVirtualDeviceFileBackingInfo).GetVirtualDeviceFileBackingInfo().Datastore,
    },
}

vm.EditDevice(ctx, vmrootdisk)

...but vCenter is returning:

"error": {
  "fault": {
    "property": "virtualDevice.backing",
    "deviceIndex": 0,
    "badFileOp": "replace"
  },
  "localizedMessage": "Invalid operation for device '0'.",
  "Description": {
    "key": "com.vmware.vim.vpxd.vpx.vmprov.ReconfigureVm",
    "message": "Reconfiguring Virtual Machine on destination host"
  }
}

I feel like I'm close.

[rickatnight11]

I didn't manage to figure this out, but I did finally get RemoveDevice + AddDevice working, borrowing heavily from govc's device.remove and vm.disk.attach implementations. It's slightly annoying, because I end up needing to removing all disks and adding them back to maintain the original label order (i.e. "Hard disk 1", "Hard disk 2", etc), but it works! Would still love any feedback on cleaner/preferred ways to do this.

[github-actions]

This issue is stale because it has been open for 90 days with no
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[rickatnight11]

/remove-lifecycle stale