Etherwake is not working, it's bugged, only capable of writing two error messages

[disc]

When i specify MAC address only:

etherwake: The Magic Packet host address must be specified as
  - a station address, 00:11:22:33:44:55, or
  - a hostname with a known 'ethers' entry.

or if i specify interface too:

SIOCGIFHWADDR on eth0 failed: No such device

etherwake should be removed from repository, as it's not working at all.

[G D (gmdubuntu)]

I think it is working fine.

By default it assumes your network interface exists i.e. eth0, otherwise you'll get "SIOCGIFHWADDR on eth0 failed: No such device" response

However on my installation 20.04.2 LTS, my network interface is enp4s0f0.

Try:
$ sudo etherwake 00:11:22:33:44:55 -i enp4s0f0

This currently works fine with my network setup...

GD

[G D (gmdubuntu)]

Just for reference version I am using is

$ etherwake -v
etherwake.c: v1.09 11/12/2003 Donald Becker, http://www.scyld.com/