NICs: TOE (TCP Offload Engine) vs TCO (TCP Checksum Offload) in an iSCSI environment
Posted on 2011-05-02
I have a pair of HP DL360 G5's that I need to connect to a Dell Equallogic PS4000 SAN. I am looking for a compatible NIC to put into these servers to allow for the most efficient means of communication between the SERVERS and the SAN. HP has pointed me in the direction of HP NC364T, which is a 4 port half height (required in this server) card that supports TCO. To date, every card that I have ever connected to an Equallogic SAN with has had TOE, not TCO. HP support is telling me that this should be the same for this particular application.
Can anyone tell me if TCO is sufficient for an iSCSI environment to take the TCP overhead off of the processor / OS the way that TOE does? We have tried my favorite cards, the Broadcom netExtreme II 5709, and this did not seem to work well with the HP hardware (we usually use them in Dell).
Any insight is appreciated. Thanks.