Description of problem:

This is a request to add a `diag` option to fence_vmware_soap, analogous to the one used in fence_ipmilan. The idea is to send an NMI to the guest, in order to trigger a panic and collect a vmcore.

This appears to be possible with the SendNMI endpoint for the SOAP API.

• https://code.vmware.com/apis/42/vsphere/doc/vim.VirtualMachine.html#sendNMI

As much as I would love to add this feature to fence_vmware_rest, as far as I can tell this feature is missing from the REST API. If someone finds a way to send an NMI via the REST API, then let's try to add this in the REST agent.

• https://developer.vmware.com/docs/vsphere-automation/latest/vcenter/operation-index/

Version-Release number of selected component (if applicable):

fence-agents-vmware-soap-4.2.1-53.el8_3.1

How reproducible:

N/A / always

Steps to Reproduce:

Run fence_vmware_soap with `-o diag`.

Actual results:

1. fence_vmware_soap -a vcenter.gsslab.brq.redhat.com -l gssuser@gsslab.brq -p <pw> --ssl-insecure -o diag -n my-vm-name
   2021-01-21 18:25:52,338 ERROR: Failed: Unrecognised action 'diag'

2021-01-21 18:25:52,339 ERROR: Please use '-h' for usage

Expected results:

An NMI is sent to the VM. If kdump is configured and the guest OS is configured to panic on NMI, then a vmcore is generated.