|20gb? typo since you don't mention 10Gbe?|
TommiGun your topolgy description is a bit vague. I am going to assume the 1gb nics are on one switch or vlan and the other backend nics are on another.
Given this setup there is no "routing" since you would have two different independent subnets accessing these servers. The "backend" would be accessed from those devices on that subnet. Same would be true for the "frontend".
Perhaps you can clarify a bit what it is you are trying to accomplish and why?
guapo can you explain what you are thinking here?
"you can try to make the backend NIC the default gateway of the front as long as the two NICs are on the same subnet"
Windows will not use both nics. It will only use one if in the same subnet/switch [which is why we do adapter teaming] so this isn't making sense to me.
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