Sergey is working on a spec to use the standardized virt driver instance
diagnostics in the os-diagnostics API. A question came up during review
of the spec about how to define a disk 'id':
The existing diagnostics code doesn't set a disk id in the list of disk
dicts, but I think with at least libvirt we can set that to the target
device from the disk device xml.
The xenapi code for getting this info is a bit confusing for me at
least, but it looks like it's possible to get the disks, but the id
might need to be parsed out (as a side note, it looks like the
cpu/memory/disk diagnostics are not even populated in the
get_instance_diagnostics method for xen).
vmware is in the same boat as xen, it's not fully implemented:
Hyper-v and Ironic virt drivers haven't implemented
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