Arch Linux: systemctl dhcpcd netcfg problem

I think the Arch Linux dhcpd / dhcpcd thing is kinda broke...
I read many installation guide which says to start dhcp use the following command but it NEVER works for me:

# systemctl enable dhcpcd@.service 

eth0 or enp2s1 whatever won't work.  I don't know what the heck is enp2s1 in my system...

Anyway, this is what I do to fix it(mine is just VMware NAT network):

1. cp /etc/network.d/examples/ethernet-dhcp /etc/network.d/mynetwork
2. vi /etc/network.d/mynetwork  , modified line INTERFACE='enp2s1'
3. try in root, netcfg mymetwork, see if it can fetch IP properly
4. if everything looks good, # systemctl enable netcfg@mynetwork

It should create the symbolic link.  Then reboot to see if it works properly...