Starting with Rocks 4.3, the frontend must be configured to tell a node to re-install at the next PXE boot. This action is controllable on a per-node basis. At the end of successful installation, the node requests the frontend to set its PXE boot to os. To re-install a node using PXE (e.g. compute-0-0), then do the following:
# rocks set host boot compute-0-0 action=install # ssh compute-0-0 "shutdown -r now"
If the boot order has not been set to PXE first, you can force a PXE boot with the local keyboard, or by calling /boot/kickstart/cluster-kickstart-pxe on the local node.