Network teaming is useful for providing redundancy and increasing network capacity for servers. Traditionally, the downside has been getting it set up — often requiring the installation of non-native drivers for the network interface cards (NICs).
VMware ESX NIC Teaming
VMware ESX ships with the ability to connect multiple NICs to a single vSwitch–right out of the box. No additional drivers or configuration needed. You just need to click a few buttons to add the additional NICs. You end up with something like this:
There are several advanced configuration options available, but for the most part it “just works” and can be set up very quickly. This is one of the many great benefits of virtualizing your server hardware–individual virtual machines benefit from enhanced network redundancy without any additional configuration in the guest OS. Plus, it works for all guests, regardless of OS vendor.
Hyper-V NIC Teaming
How does Hyper-V handle NIC teaming? They punt and leave it up to the hardware (server and/or NIC) manufacturers. This puts the system administrator in an unpleasant situation. Take, for example, this thread on Mark Minasi’s Forum. That is not an isolated incident, as you can see.
Since this feature is up to the server vendor, let’s see what one of them has to say about it. According to this HP integration note, dated January 2009:
Windows Server 2008 Hyper-V does not support the Network Configuration Utility (NIC Teaming). Deselect this component before installing the PSP components.
Ouch. But wait–HP just published a HOWTO paper on the topic. Perhaps things are changing. Evidently, the installation order of the teaming drivers and Hyper-V is critical:
If the teaming software is installed first, the network adapters may cease passing traffic. The resolution to this issue is to uninstall both the HP teaming software and Hyper-V, reboot the server and then reinstall Hyper-V and the teaming software.
But this is my favorite part (Server Core fans, take note):
Uninstalling teaming software
If HP ProLiant Network Teaming Software is already installed on a server, it must be removed (uninstalled) prior to installing and enabling Hyper-V.
There is no known method of uninstalling HP ProLiant Teaming software on machines running Windows Server 2008 Server Core. A tool for removing the teaming software is under development and will be available on the HP website in the future. HP recommends that any machine designated to run Server Core, Hyper-V, and teaming be configured as such during the initial installation, using the specified order of installation described above.
Even if Hyper-V is “free” and the HP NIC teaming drivers are “free,” your time is valuable. Do you want to spend it configuring your hypervisor host OS, or getting real work done for your customers?
Please note, the purpose of this article is to highlight the state-of-the-art in hypervisor NIC teaming — not knock HP. I am very satisfied with the HP Proliant servers that I use every day. They run ESX like a champ!