Just for reference, to reboot an SP from GUI, please use the option from the relevant SP.
Right-click on the SP to bring up the sub-menu where you will find reboot.
Also note that Write Cache should be disabled before rebooting an SP. Ensure that 1 SP reboot completes and the array does not report any further errors or faults before rebooting the peer SP.
Navigate to Array -> System -> Hardware -> Storage Hardware
Should the array or an SP be powered off, someone will have to go to site to power it on again.
