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NIC Bonding Not in Hyper-V

I recently blogged about the issue of "NIC teaming", also known as "NIC bonding", and the fact that it's allegedly missing from Hyper-V. Virtualization blogger Scott Lowe originally reported this, and we have confirmed that it is not a feature of Microsoft's new hypervisor. Here's the response, from Microsoft's Robb Mapp:

"NIC Teaming is a capability provided by our hardware partners such Intel and Broadcom. Microsoft supports our partners who provide this capability. This is true whether the customer is running Windows, Exchange, SQL Hyper-V, etc. We'll have a detailed KB article about this coming out soon."

So Hyper-V doesn't do it, but you can buy products that do it -- although not all of them do. I went back to my go-to virtualization analyst, Chris Wolf, for his take on how this could affect the market for Hyper-V. Here's what he said:

"This is a pretty big issue, and one that I've been raising with Microsoft for months. NIC teaming is a requirement in virtualization deployments, in my opinion, as there should be no single points of failure that could potentially disrupt access to several VMs.

Now if you think about it, the need for teaming is nothing new to Microsoft. I've been deploying Microsoft clusters with teamed NICs for years. The NIC vendors would support their own teamed configuration and that was good enough for me. So basically, it's the same issue with Hyper-V. Microsoft may not officially support the teamed configuration, but the vendor that provides the NIC driver will. Microsoft even has a KB article about this.

Compare this to storage and there are a lot of similarities. Microsoft officially supports multipath storage drivers, and when it comes to troubleshooting low-level storage issues, the storage HBA vendor will get involved. It should be the same process with network interface vendors.

Comparing VMware to Microsoft, I can team any two NICs using VMware ESX, so I don't need to go out and buy specific NICs that include a teaming driver. The Microsoft implementation would require a pair of NICs and a teamed driver, so the NIC teaming would be managed independently of the hypervisor.

At the end of the day, I can achieve the same level of network availability in both hypervisors (ESX and Hyper-V). However, Microsoft can do more in this area. Since I can still achieve teaming in Hyper-V, I don't see the issue as a deal breaker. I'm sure Microsoft will do more with teaming down the road, but Hyper-V is a first generation product, so it's fair to expect Microsoft to take some time to develop such features. In the meantime, the features are there, but just implemented differently."

My take: NIC teaming should be included in the base hypervisor, period. If Hyper-V truly wants to compete with ESX -- and more competition for VMware is something everyone should want -- this needs to be added as a feature.

Posted by Keith Ward on 06/18/2008 at 12:48 PM


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