That did the trick ! Thanks.
Another similar question, I tried doing a network boot on a third machine.
It found the core and got issued the ip 192.168.80.2.
However it wasn't able to mount the image correctly. I assume this is because the core only has one nic with ip 192.168.1.17 (and 192.168.80.1), i'd probably have to do something funky with the route table ?
You should not have to do anything to the routing table to add a 3rd MD (or any number of additional MD's). However based on the 80.2 address this looks like it is your 1st MD that your adding.