winntfs

Some highly knowledgeable folks at Microsoft recently shared some very valuable tips during the recently concluded MVP Summit. This blog is a small sample of thse tips.

Prior to Windows 8, NIC Teaming has been a feature never officially supported by Microsoft. It was a third party offering from an OEM/IHV/ISV and all support for the feature had to be provided by the third party. I personally have spent considerable time debugging situations where a system start up service I wrote had issues. It turned out that my service could not connect to the Domain Controller because the NIC team was still in the forming stage and had not yet completed its initialization.

Windows Server 8 natively supports NIC teaming. Here are the highlights and tips:

• NIC teams can only be formed between homogenous NICs. So two 1GB NICs can be teamed, or two 10GB NICs can be teamed, but you cannot team a 1GB and 10GB NIC.
• If the individual NIC members each support Receive Side Scaling (RSS), the NIC team also supports RSS. Hence it is a good idea to team NICs that support RSS. The resulting NIC team is also highly capable and does not lose any functionality.
• If the individual NIC members each support RDMA, the resulting NIC team does NOT support RDMA. Given how Windows 8 SMB 2.2 natively supports RDMA without modifying applications, it is a bad idea to team NICs with RDMA capabilities, and where the interconnect (routers, etc) also supports RDMA