VM reconfiguration error: VM attachment to NSX or vMotion of an NSX-connected VM

Products

• VMware NSX
• VMware vSphere ESX 8.x

Issue/Introduction

• For a host which doesn't allow VM attachment to an NSX segment or subnet, or doesn't allow inward migration of an NSX-connected VM, Either vSphere vMotion shows a blocking network compatibility failure such as
  
  

  "Currently connected network interface" 'Network adapter #' uses network 'DVSwitch[## ## ## ## ## ## ## ##-## ## ## ## ## ## ## ##] NSX port group [dvportgroup-##](nsxa down)', which is not accessible.

  
  
  
• Or looking at the ESXi vpxa.log may show either:
  
  

  vim.VirtualMachine.reconfigure: :vim.fault.PlatformConfigFault
   --> message = "Failed to attach virtual network interface Unknown to logical switch ########-####-####-####-############, message from NSX: No response from NSXA"
   --> text = "Failed to attach VIF"
   --> msg = "An error occurred during host configuration: Failed to attach VIF."

  or

  vim.VirtualMachine.reconfigure: :vim.fault.PlatformConfigFault
   --> message = "Failed to attach virtual network interface Unknown to logical switch ########-####-####-####-############, message from NSX: Failed to send VIF RPC request. Please check if the connectivity between Host and NSX Manager is up."
   --> text = "Failed to attach VIF"
   --> msg = "An error occurred during host configuration: Failed to attach VIF."

   

• Or this message from NSX:
  
  

  "No response from NSXA" 
  --> text = "Failed to attach VIF" 
  --> msg = "An error occurred during host configuration: Failed to attach VIF." or vim.VirtualMachine.reconfigure: :vim.fault.PlatformConfigFault 
  --> message = "Failed to attach virtual network interface Unknown to logical switch ########-####-####-####-############
  
  "Failed to send VIF RPC request. Please check if the connectivity between Host and NSX Manager is up." 
  --> text = "Failed to attach VIF" 
  --> msg = "An error occurred during host configuration: Failed to attach VIF."

Environment

• VMware ESXi 8.x, 9.x
• VMware NSX

Resolution

1. Login to the NSX-Manager UI and confirm if there is any connectivity issues between the NSX-Manager and the ESXi hosts where the affected VMs are placed or are being vMotioned to.
   • Navigate to System > Fabric > Hosts
   • If any hosts are in disconnected and failed state, that has to be fixed from the NSX side.
     
     
2. For each impacted ESXi host,
   
   • ssh to the host and log in as root.
   • Check if the nsxa service is up by running:
     net-dvs -l | fgrep component.nsxa
     
     
   • If the response is: com.vmware.common.opaqueDvs.status.component.nsxa = down , propType = CONFIG
   • Then restart opsAgent by running:
     /etc/init.d/nsx-opsagent restart
     
     
   • If NSX still views the host as disconnected, then also run:
     /etc/init.d/nsx-proxy restart