This issue was a bad incident which we faced in one of my clients environments. vCenter was not accessible due to a hardware failure and the entire environment was configured using the distributed switches. vCenter was recovered with a backup and registered in an ESXi host, but connectivity to a distributed port was not successful. This is my personal experience and this how I resolved it.
When I was trying to add the vCenter to the distributed port group it was throwing the below error message. I know, it’s a configuration option in distributed portgroup, but it is not the time to change the configuration.
Addition or reconfiguration of network adapters attached to non-ephemeral distributed virtual port groups is not supported.

So I decided to create a standard switch in the ESXi host and add an uplink which is consumed by the distributed switch. The available throughput and the redundancy will be impacted, but recovering the vCenter was crucial at this point.
Command line tools can easily be used in this scenario and you can either use the GUI interface, I preferred to use the command line.
I created a new Standard Switch Portgroup called “VMnetwork” with the below command
esxcfg-vswitch -A VMnetwork vSwitch0
If you don’t have a Standard vSwitch available you can create it, using below command
esxcfg-vswitch -a [vSwitch_name]
Checked the Standard Switch portgroup creation and the Distributed Switch Uplink assignment with below command and also the distributed port ID (DVPort ID) connected the uplinks
esxcfg-vswitch -l

Removed the uplink from the Distributed Switch. In my case vmnic2 which was assigned to the 9967 port
esxcfg-vswitch -Q -v 9967 [distributed_switch_name]

Added the uplink to the created Standard Switch using the below command
esxcli network vswitch standard uplink add --uplink-name=[vmnic_name] --vswitch-name=[vSwitch_name]

Checked the switch status and the uplink assignment again

Once the Standard vSwitch is created and assigned the uplink, I connected the recovered vCenter to the created portgroup and restore the connectivity. Migrating the Standard Switch portgroup to Distributed Switch portgroup can be performed later and uplinks can be reconfigured.
Again, this is how I resolved it and if you think you have some other workaround or fix to the same situation feel free to share it in a comment.
GoatboyX
May 22, 2019Aruna, we had a VDI environment down until I read this thank you soooo much for this article.
Aruna Lakmal
May 24, 2019Hey! Wonderful news!
I’m happy that I could help you.
Anh Tran
November 10, 2019Hi Aruna, this is helpful, exact the same situation I’m dealing with. But unfortunately, in my case, there is an addition problem is the ESXi host cannot find filter vmware-sfw for reconfiguring VM.
I got this log from vmkernel.log:
2019-11-10T13:07:01.677Z cpu31:10300999)Net: 2456: connected vm-man-vcenter eth0 to VMnetwork, portID 0x5000007
2019-11-10T13:07:01.677Z cpu31:10300999)DVFilter: 3626: Could not find filter ‘vmware-sfw’
2019-11-10T13:07:01.677Z cpu31:10300999)DVFilter: 5669: Failed to add filter vmware-sfw on vNic 0 slot 2: Not found
2019-11-10T13:07:01.677Z cpu31:10300999)Net: 3712: disconnected client from port 0x5000007
2019-11-10T13:07:01.677Z cpu31:10300999)WARNING: Net: 2761: connect to vswitch VMnetwork from world 10301000 failed: Failure
Did you meet this issue before? Could you advice me?
Thank you so much!
Anh Tran
November 10, 2019Hi Aruna, this is helpful, exact the same situation I’m dealing with. But unfortunately, in my case, there is an addition problem is the ESXi host cannot find filter vmware-sfw for reconfiguring VM.
I got this log from vmkernel.log:
2019-11-10T13:07:01.677Z cpu31:10300999)Net: 2456: connected vm-man-vcenter eth0 to VMnetwork, portID 0x5000007
2019-11-10T13:07:01.677Z cpu31:10300999)DVFilter: 3626: Could not find filter ‘vmware-sfw’
2019-11-10T13:07:01.677Z cpu31:10300999)DVFilter: 5669: Failed to add filter vmware-sfw on vNic 0 slot 2: Not found
2019-11-10T13:07:01.677Z cpu31:10300999)Net: 3712: disconnected client from port 0x5000007
2019-11-10T13:07:01.677Z cpu31:10300999)WARNING: Net: 2761: connect to vswitch VMnetwork from world 10301000 failed: Failure
Did you meet this issue before? Could you advice me?
Thank you so much!
Aruna Lakmal
November 11, 2019Hi Anh
Thank you very much for your comment!
Honestly, no I haven’t met with this issue. By looking at the error it seems vNic 0 slot 2 is not a valid option, did you check it again? Once you listed the ports were you able to see the referring port?
Brian Tabor
September 19, 2020Aruna,
Thank you so much for your article. I was having the same issue when trying to set the distributied port group for the vCenter (7.00b) I was moving from one environment to another. I followed your instructions and everything is back up and ready to good!
Brian
Aruna Lakmal
September 20, 2020Hey Brain
Thank you very much for your words and that is indeed the purpose of my blog. Thank you for stopping by.
Dan Newman
October 6, 2020I had a similar issue trying to isolate an IP conflict error.
I temporarily disconnected the vCenter NIC, but was then unable to re-enable it
I was able to un-register the VM and edit the vmx file directly by changing FALSE to TRUE in the line:
ethernet0.startConnected = “FALSE”
The other network settings had been undisturbed so this did the trick.
Dan Newman
October 6, 2020Scratch that. ESXi acts like it’s going to work, but the NIC remains disconnected
MM
November 6, 2020very usefull thanks.
in this line “esxcfg-vswitch -Q -v 9967 [distributed_switch_name]” please type name vmnic name
Petr
August 11, 2021Thx , very useful
Only one missing paramater : esxcfg-vswitch -Q vmnic2 -v 9967 [distributed_switch_name]
Vusal Garayev
November 21, 2022Thanks