Barix address DHCP weirdness?

[ard jonker]

Is anyone familiar with the DHCP protocol?

I lost the Barix a few hours ago and only with a lot of effort, I've got it back, sort of.
I have the impression that either I'm doing something wrong, or the Barionet is misbehaving.

On my mac 10.10.3 server 4 that runs DHCP for the house, I've entered the MAC address of my Barix Barionet.
On the bottom of the Barionet is a label that reads '00204AB8180E'.
In my DHCP server setup, I've set a static IP address of 192.168.178.22 and a MAC address of 00:20:4a:b8:18:0e

and I cannot reach the Barix at http://192.168.178.22 as would (imho) be logical, but on http://192.168.178.60.
In the Barionet, I've set the IP address to 0.0.0.0, as in the Network tab of the Settings page it reads "(0.0.0.0 for DHCP)"
The netmask, gateway, dns server are all 0.0.0.0 and the DHCP hostname is Barix
When I reboot the Barix (powercycle) in the DHCP service log I see

interface en0: ip 192.168.178.199 mask 255.255.255.0
DHCP REQUEST [en0]: 0,42:61:72:69:78 <Barix>
ACK sent Barix 192.168.178.60 pktsize 300

All other devices do their DHCP request with the MAC address I find in their 'hardware' tab of the Network preferences.
They nicely get the IP address I set aside as static in the Clients tab of the DHCP server settings.

What am I doing wrong? Is the 0,42:61:72:69:78 telling me that the sticker in the bottom is wrong?
When I enter 00:42:61:72:69:78 in the MAC address field of the Server, it still doesn't work.

Ard