How do you get 20Gbit from a dual port NC522SFP on a DL580 G7

[20Gbit]

Hello gurus,

We can easily get 10Gbit on a single port of a dual-port NC522SFP NIC card - on a DL580 G7.

However - when starting to transmit to the second port - the first port throttles down - and the sum total of both ports can't seem to exceed about 5 Gbit.

Is this the card? The firmware (we have the latest)? an OS limitation (Oracle/RHEL Linux)? The switch (Nexxus 5K) ?

Thoughts?

Thank  you !

[scharchouf]

under Windows you need to creat NIC Teaming, fot RHEL is Bonding, Channel bonding enables two or more network interfaces to act as one, simultaneously increasing the bandwidth and providing redundancy.

[20Gbit]

Thank you.

Yes, bonding is an option - but requires allowing bonding at the switch - which is not an option for us at the moment.

So - we gave each NIC port its own IP and subnet - and are sending data concurrently to both ports - as if they were 2 independent NIC cards.

In other words - we are assuming that a single 2-port NIC can be made to behave like two 1-port NICs. That's the key question.

Trying to establish whether streaming 2 independent 10Gbit streams to the 2 ports is being governed down by the NIC card, by the firmware, by linux, or by the switch.

???