This one was one hell of a problem I ever worked on. Took me almost 2 years to get around it. Solved it a month back, got time to write today.
Think of this:
1 iscsi target, 1 windows image to serve on tftp. Multiple nodes that boot from it. It will work fine until all the nodes have exact same config. Change network card of 1 and it will fail to boot. Its fine. Windows needs network adapter to boot over iscsi and if there is no driver for this different adapter then it will die. Makes sense.
Problem was, even after installing different drivers [which is not_so_straight_forward_either ] Windows won’t boot. There are some LWF [Light weight Filter] binding issues that won’t let it happen. Theoretically, if you get rid of these bindings, it should work. Took a long time to realize all the parts of it.
and I was able to boot over iscsi even after changing n/w adapter ! So, here are my notes, might save one’s time. There are products like CCBoot that have solved this problem already but all of these tools are commercial.