I've just setup a nice intel-based mini-server, and I'm wondering how the various functions of wake-on lan work.
From the manpage: wol p|u|m|b|a|g|s|d... Set Wake-on-LAN options. Not all devices support this. The argument to this option is a string of characters specifying which options to enable. p Wake on phy activity u Wake on unicast messages m Wake on multicast messages b Wake on broadcast messages a Wake on ARP g Wake on MagicPacket(tm) s Enable SecureOn(tm) password for MagicPacket(tm) d Disable (wake on nothing). This option clears all previous options.
But what do each of those options mean? Can I wake a computer by pinging it when the wol "u" setting is activated? How will the router / network switch know where to send the unicast message if the computer is asleep?
I guess that depends on the arp cache. But also, these are simple network messages, in my case anyway. The u and b settings didn't require a magic packet at all, just a ping sufficed.
So for activating everything, I'm testing to ensure that wake-on-lan is enabled for sleep state 3: cat /proc/acpi/wakeup | grep 'ILAN' | awk '{ print $3; }'