If you get the error while try to commission or wake on lan,
you will need to check first if you have it installed on your server (MAAS server).
if you check the template:
/etc/maas/templates/power/ether_wake.template
you will see that it looks for:
/usr/bin/wakeonlan
and
/usr/sbin/etherwake
just install them:
apt-get install etherwake wakeonlan -y
and if you want to test it for each node: i = interface and b = broadcast
/usr/sbin/etherwake -i <INTERFACE> -b <MAC>
/usr/sbin/etherwake -i eth0 -b e8:39:35:39:e3:11
Enjoy,