Virtual machines lose network connectivity in NSX 6.2.x

Products

• VMware NSX

Issue/Introduction

Upgrading to NSX for vSphere 6.2.4 resolves the issue.

Symptoms:

In the default gateway when the pMac of DLR is the MAC address instead of generic DLR MAC address, Windows virtual machines lose network connectivity.

Note: For additional symptoms and log entries, see the Additional Information section.

Environment

VMware NSX for vSphere 6.2.x

Resolution

This issue is resolved in VMware NSX for vSphere 6.2.4.

 

To work around this issue if you do not want to upgrade, use one of these options:

• Configure the static ARP for the default gateway within the guest operating system of the virtual machine.
• Disable the ARP Suppression and ARP Proxy. To disable the ARP Suppression and ARP Proxy, contact VMware Support and note this Knowledge Base article ID (2146293) in the problem description. 

Additional Information

You experience these additional symptoms:

• When you run the net-vdr -C -l command in the ESXi host, you see entries similar to:
  
  Host locale Id: 421b0a09-6c98-293c-ac15-89ab05XXXXXX
  
  Connection Information:
  -----------------------
  
  DvsName VdrPort NumLifs VdrVmac
  ------- ------- ------- -------
  NSwitch vdrPort 5 X:X:X:X:X:X
  Teaming Policy: SrcPortId Hashing
  Uplink : Uplink 1(100663301): X:X:X:X:X:X(Team member) <--------pMac
  Uplink : Uplink 2(100663299): X:X:X:X:X:X(Team member) <------- pMac
  
  Stats : Pkt Dropped Pkt Replaced Pkt Skipped
  Input : 0 0 315452397
  Output : 39749 22 1037595966
  
  Note: Each ESXi host has a unique set of pMac depending on the number of uplinks. However, the vdrport MAC is same on every ESXi host.

• When you run net-vdr -C and arp -a commands, the pMac address information displayed must be different.
  
  Note: The default gateway in the guest operating system must not be the same as the pMac.