The form for editing BDB HA VHN does not populate reliably the UI controls with current attribute values. Some of the attribute controls can be left unset. As result, on submitting the form, null/empty values can be sent as part of update request to the broker.
Editing of attributes cannot be done reliably from WVM, as when the issue occurs, the update requests from WMC fail due to broker side validation. There is a possibility of unexpected change of attribute value to null.
Work around: REST API can be used to change the attribute values.