When editing or creating a VMK adapter on an ESXi host under the host network configuration, some or all services are greyed out and cannot be selected.
vSphere - all versions
This happens when any VMK adapter is configured in an IP stack other than the default.
For services tied to the IP stack that is in use, that service will no longer be available in the default stack.
And the VMK adapter that is in the alternate stack will only be able to use the service that is tied to that stack.
This is expected behavior. If you need to add a VMK adapter to a service that is greyed out, verify that there is already a VMK adapter using the specified IP stack and place the new or edited VMK adapter there.
If you need to use the VMK adapter for multiple services, it must be placed in the default IP stack and the proper services selected.