Virsh commands timing out

Continuing to see timeouts when running virsh commands. Either when opennebula is running them, or when I’m manually running them. This happens when shutting down a VM or booting a VM. It will take several minutes for OpenNebula to recognize that a VM has been shutdown.

Mon Aug 20 11:39:03 2018 [Z0][VMM][I]: error: Failed to destroy domain one-130
Mon Aug 20 11:39:03 2018 [Z0][VMM][I]: error: internal error: connection closed due to keepalive timeout
Mon Aug 20 11:39:03 2018 [Z0][VMM][I]: error: One or more references were leaked after disconnect from the hypervisor

Versions of the related components and OS (frontend, hypervisors, VMs):

OpenNebula 5.6.0
Hypervisor: Ubuntu 16.04

Steps to reproduce:

Shutdown a VM
Run sudo virsh list on the VMs hypervisor.

Current results:

The command hangs, and it takes several minutes for OpenNebula to recognize that the VM has been shutdown.

Expected results:

The command succeeds, and OpenNebula updates the status of the VM in under a minute.