Green eth0 down, hardware error - new green eth4 no internet access

NethServer Version: 7.5
Module: your_module

Hello Guys,

we´ve got a small trouble with our nethserver.

The PC has a quad core i7 930, 24gb of ram, and 7 nics in total.

configured a quad nic for everything. 3x red (for multiwan) and 1x green.

it seems, that i have a hardwarefault in the green interface, now i connected a new green pci networkcard.
the eth0 connects and disconnects all time.

first interface: 172.0.0.254
i configured the 2nd green interface: 172.0.0.253.

the two greens are not in the same network.

I disabled the dhcp on the first green eth0, but i still gain my ip from nethserver.
eth4 (2nd. green) dchp enabled, on the clients everything looks quite good, but there is no internet access.

the red interfaces are all on dynamik and are getting the ip´s from the routers.

how do i get the eth4 running?

thank you alot.

This puzzles me a bit because they have the same subnet (172.0.0.0.) assigned:

As Far as I know different networks must have different subnets. This make a kind of sense : how can the (internal) router decide to which network replies/requests need to be routed to if the have the same subnet?

Maybe I did not fully understand your setup, if so can you clarify a bit more?

Why not simply free the role and assign it to the new network card?