The ability to power on a system over the network using Wake-on-Lan (WoL) can be extremely useful, especially if you are not physically near the system or after a power outage. I personally have been using the wakeonlan utility on my macOS system for several years now.
The syntax is super easy, you just provide the MAC Address of your system:
wakeonlan 54:b2:03:9e:70:fc
Sending magic packet to 255.255.255.255:9 with 54:b2:03:9e:70:fc
I recently came to learn that ESXi itself has the ability to send a WoL packet from the ESXi Shell! This could be handy without having to install WoL client, especially if you have access to an ESXi host.
vsish -e set /net/tcpip/instances/defaultTcpipStack/sendWOL 192.168.30.255 9 54:b2:03:9e:70:fc vmk0
This uses the not supported vsish CLI to send WoL packet. The first argument is the network broadcast address, so if you have a network of 192.168.30.0/24, then the address would be 192.168.30.255. The second argument is a value of 9, which is probably related to the magic packet as you can see the same value from the wakeonlan utility abvoce. The third argument is the MAC Address of the system and finally the fourth and final argument is the ESXi VMkernel interface to send the packet out of.
It'd be nice if there were a daemon on the host that listened for WoL magic packets directed to known MAC addresses of VMs and that then automatically powered them on accordingly.