Flexible to Enhanced vmxnet adapter, should I change?

[HendersonD]

All of my virtual machines run Windows Server 2003, most standard edition 32 bit but a few enhanced and few 64 bit. All of them use Flexible network adapters.Will I get a performance boost by changing them all to use the enhanced vmxnet adapter?

This article describes how to change the adapter:

http://kb.vmware.com/selfservice/viewContent.do?externalId=1007195&sliceId=2

Why is it necessary to change the OS to Server 2003 Enterprise 64 bit in order to add the enhanced adapter? Once choosen, before powering up should I change back the choice of OS to the proper one? The article does not say to but it seems like the logical thing to do.

[Lightbulb · Accepted solution]

From KB

Enhanced vmxnet — The enhanced vmxnet adapter is based on the vmxnet adapter but provides some high-performance features commonly used on modern networks, such as jumbo frames. This virtual network adapter is the current state-of-the-art device in virtual network adapter performance, but it is available only for some guest operating systems on ESX Server 3.5. This network adapter will become available for additional guest operating systems in the future.

So good to have generally, you can test it on one system and see.

Why change the OS settings? I don't know, where I work we use a custom OS deployment system that only works with flexible adapters, so for Windows 2003 64bit systems we create the VM shell as Windows 2003 32 bit so we can chose the flexible adapter type. Then at a certain point in the provisioning process we switch back to the proper OS definition and add e1000 or Enhanced vmxnet adapter.

Yes change the OS setting back to previous values once the new adapter has been added

Remember to backup IP settings prior as you may have to reenter them on new adapter.

[Lightbulb]

Also check out this blog post

http://blog.scottlowe.org/2008/12/15/enabling-enhanced-vmxnet/