Unable to RDP( Remote Desktop Protocol) to the Windows Virtual machine connected over HCX L2E (Layer-2 extended) segment.

Products

• VMware HCX
• VMware NSX

Issue/Introduction

• ICMP or Ping reachability from source to impacted VM works.
• RDP connection fails to establish towards TCP port 3389, regardless of residing on any ESX host. 
• Windows Firewall or any 3rd party Guest OS firewall is disabled.
  
• RDP service is running.
  

Environment

VMware NSX
VMware HCX

Cause

Packet captures on the impacted VM's Guest OS confirms, the TCP SYN packet being received by the source VM but no TCP SYN,ACK response is being responded by impacted VM (Virtual Machine). 

 

Resolution

The issue appears to be outside the scope of ESXi or the virtual machine itself. We recommend contacting the Guest OS vendor for further assistance.

Workaround: A new VM was created with the same Guest OS to use same vLAN, and RDP functionality worked as expected.

Additional Information

Reference article