Hello [NAME]-Joey C and [NAME]-Chris H  I have found the solution about Wake On LAN (WOL) for TrueNAS Scale (Linux based): German: [URL] GRUB_CMDLINE_LINUX_DEFAULT="xhci_hcd.quirks=270336" [URL] It works, now the Dell T20 is standing down, no auto start.
Hello, what might be the reason? If I do shut down the system regardless in the WebUI or with the power button: the shutdown will be done, NIC LEDs go off briefly, be turned on after 1 second and the T20 will boot again. The only time I managed it to stay shut down was to disconnect the power cable and re-attach it. (UEFI after power loss = stay off) TrueNAS-SCALE-22.12.1 installed on SATA SSD Power and LAN cable connected to T20, nothing else SATA HDD for storage UEFI Version A20 Disable Deep SleepEnable Wake On LAN 
Dell T20 doesn't stay shut off, auto restart after shut down