NSX-T PCPU Requirements for Edges

New CPU requirements for NSX-T may leave older lab hardware out in the cold.

If you are running old hardware in your lab, you may have come across an unexpected failure while deploying your first NSX-T edge VM.


The exact error message will be something similar to:

“[Fabric] Edge <uuid> is not ready for configuration error occurred, error detail is NSX Edge configuration has failed. The host does not support required cpu features: [‘aes’].”

The edge will be successfully deployed, but will remain ‘unconfigured’ and will not allow you to add it as a transport node.

The ‘aes’ feature being referred to is Intel’s AES-NI acceleration for cryptography. You can find out more about AES-NI here. In NSX-V, AES-NI was optionally supported for offloading cryptography for VPN related features. It seems that this has now become a hard requirement for NSX-T.

Unfortunately, like vSphere 6.7, NSX-T has minimum CPU requirements that can’t be worked around. If you have a browse through the NSX-T system requirements, you’ll find a note about CPU compatibility in the “NSX Edge VM and Bare-Metal NSX Edge CPU Requirements” section. Listed there is reference to:

  • Xeon 56xx (Westmere-EP)
  • Xeon E7-xxxx (Westmere-EX and later CPU generation)
  • Xeon E5-xxxx (Sandy Bridge and later CPU generation)

This means that anything released prior to 2011 is unlikely to work, with the exception of a few Westermere EP based Xeons, which seem to have spotty success. On the AMD front, it appears that even CPUs with AES instructions will fail similarly due to a CPU compatibility check that is done during edge deployment.

My management host uses Xeon E5-2670s, which work fine, but my compute cluster uses very old Xeon X3440s that came out before AES-NI was introduced. Now that I can’t run vSphere 6.7 or an NSX-T edge on these hosts, I think it may finally be time to upgrade.

Unfortunately, it doesn’t appear that there is a workaround for this problem. If anyone does come across a way to avoid this, please let me know!