Cannot start a new Xen VPS in SolusVM: Could not find bridge device xenbr0

Symptoms 

• Fail to boot a new Xen VPS in SolusVM - it stays offline
• Upon attempting to start the VPS manually on Xen node there is an error:

  # xl create /home/xen/vm101/vm101.cfg
  ...
  libxl: error: libxl_device.c:1237:device_hotplug_child_death_cb: script: Could not find bridge device xenbr0

Cause

Network bridge is not configured on Xen Slave node.

Resolution

Configure network bridge on Xen slave node.