We have Dell M420 Blades with Dell M1000e chasiss ,the backplane has four dell pass-through switches .
On M420 we have Mezzanine card with 4 ethernet ports -
From CMC i see that those Mezzanine 4 ports are assigned as
eth1 and eth3 to C1 (back plane Pass through Switch) eth2 and eth4 to C2 (back plane Pass through Switch)
I can connect a cable to both C1 and C2 and can use eth1 and eth2 -
Question is that how to use rest of two ports i.e. eth3 and eth4 as i tried to put cables in remaining sockets of C1 and C2 but still ethtool shows link down.
Are these for redundancy ? any suggestion ?