• Cannot add a vmnic to a VMware ESXi host connected to a vSphere Districuted Switch (vDS)
  
• Adding a vmnic to a VMware ESXi host connected to a vSphere Distributed Switch (vDS) fails after upgrading from ESXi 5.5 to 6.0
• In the /var/log/vmkernel.log file on the affected ESXi host, you see entries similar to:
  
  <YYYY-MM-DD>T<time>.884Z cpu10:35971 opID=56ce4d29)WARNING: Ipfix: IpfixActivate:378: Activation failed for 'DvsPortset-1': Unsupported address family
  <YYYY-MM-DD>T<time>.884Z cpu10:35971 opID=56ce4d29)WARNING: Ipfix: IpfixDVPortParamWrite:669: Configuration failed for switch DvsPortset-1 port 67108866 : Unsupported address family
  <YYYY-MM-DD>T<time>.884Z cpu10:35971 opID=56ce4d29)WARNING: NetDVS: 2378: failed to init client for data com.vmware.etherswitch.port.ipfix on port 722
  <YYYY-MM-DD>T<time>.884Z cpu10:35971 opID=56ce4d29)WARNING: NetPort: 1579: failed to enable port 0x4000002: Unsupported address family
  <YYYY-MM-DD>T<time>.884Z cpu10:35971 opID=56ce4d29)NetPort: 1780: disabled port 0x4000002
  <YYYY-MM-DD>T<time>.884Z cpu10:35971 opID=56ce4d29)Uplink: 7266: vmnic2: Failed to enable the uplink port 0x4000002: Unsupported address family
  
  </time></time></time></time></time></time>Note: The preceding log excerpts are only examples. Date, time, and environmental variables may vary depending on your environment.

1. In vCenter Server, select the ESXi host and click the Configuration tab.
2. Go to Hardware > Networking.
3. Click Properties.
4. In the Networking Properties window, select the Enable IPv6 support on this host system option.
5. Reboot the ESXi host for changes to take effect.
   

To enable IPv6 on the VMware ESXi 6.0.x host using the vSphere Web Client:

1. In vCenter Server, select the ESXi host and click the Manage tab.
2. Go to Networking > Advanced.
3. Click Edit.
   
4. Click the IPv6 support dropdown menu and enable IPv6 support.
5. Click OK.
6. Reboot the ESXi host for changes to take effect.