NFCD behavior in ESXi 7.x and ESXi 8.x

Products

• VMware vSphere ESXi

Issue/Introduction

• NFCD behavior in ESXi 7.x and ESXi 8.x is different. 
• On ESXi 7.x, NFCD default mode is stopped and upon manual start as well it reverts to stopped state. 
  

  [root@esxi] /etc/init.d/nfcd start
nfcd started

[root@esxi] /etc/init.d/nfcd status
nfcd is not running.

• On ESXi 8.x, NFCD is in running state. 

[root@esxi ] /etc/init.d/nfcd status
nfcd is running
  
  
  

Environment

vSphere ESXi 7.x 
vSphere ESXI 8.x 

Cause

This is expected behavior of NFCD on ESXi 7.x and ESXi 8.x due to changes in the startup binaries. 

Resolution

In ESXi 7.x -

• NFCD listens only on port 902 within the vSphereProvisioning network stack and then passes the newly accepted socket to vmauthd.
• Thus, NFCD is expected to be not running on ESXi 7.x because the alternative network stack is typically not active.

In ESXi 8.x -

• NFCD behavior has changed. 
• With this change, NFCD now listens on port 902 on both for default network stack and the vSphereProvisioning network stack
• Thus, NFCD is expected to be always running on ESXi 8.x. 

Additional Information

Important Functional Clarification - 

The NFCD module itself does not implement NFC (Network File Copy). Its role is limited to accepting a new incoming connection and handing off that connection to vmauthd for further processing. 
Thus, the stopped state of NFCD on ESX 7.x, doesn't impact any functionality/operations of NFC, like, cloning, SRM failover, cross vCenter migration etc.