Cannot generate Xen VM kdump on Xenserver 7

I am trying to generate a kdump file of a VM running Centos 7 (HVM) on Xenserver 7.

I followed the following steps.

per link : https://docs.citrix.com/content/dam/docs/en-us/xenserver/xenserver-7-0/downloads/xenserver-7-0-vm-users-guide.pdf (page 80)

xe vm-list name-label=<name> params=uuid --minimal

xe vm-param-set uuid=<vm_uuid> actions-after-crash=preserve

For HVM guests, run the following command on dom0: <<< I had to google correct command for this part

/usr/sbin/xen-hvmcrash <vm-domid>

After running the crash command the VM halts and no dump file ever gets generated....

Per the link Preserve should "leave the VM in a paused state (for analysis)" but the VM just halts/shutsdown

Can anyone help with this? Or is there something else I need to do to setup kdump on Xenserver 7 for VMs?