Keycloak install problem

trying to install keycloak version 22.0.3-ucs1 on a UCS system which is version is 5.0-5 errata821 consisting of a primary and a secondary nodes. app installed OK, but join script failed to complete.
It get the following error, and cannot get to the bottom of what could be wrong.
ucs realm deleted within keycloak admin, and trying to recreate the default ucs realm.

root@dc1:~# univention-keycloak --binduser=admin --bindpwdfile=/etc/keycloak.secret init
Using bind-dn:
Check if init is needed: yes, continuing init
Traceback (most recent call last):
  File "/usr/sbin/univention-keycloak", line 2484, in <module>
  File "/usr/sbin/univention-keycloak", line 2480, in main
    return opt.func(opt) or 0
  File "/usr/sbin/univention-keycloak", line 2252, in init_keycloak_ucs
  File "/usr/sbin/univention-keycloak", line 427, in create_SAML_client
    endpoints = extract_endpoints_xml(client_id, opt.metadata_file, opt.no_ssl_verify)
  File "/usr/sbin/univention-keycloak", line 400, in extract_endpoints_xml
    xml_content = requests.get(metadata_url, verify=no_ssl_verify).content
  File "/usr/lib/python3/dist-packages/requests/", line 75, in get
    return request('get', url, params=params, **kwargs)
  File "/usr/lib/python3/dist-packages/requests/", line 60, in request
    return session.request(method=method, url=url, **kwargs)
  File "/usr/lib/python3/dist-packages/requests/", line 521, in request
    prep = self.prepare_request(req)
  File "/usr/lib/python3/dist-packages/requests/", line 464, in prepare_request
    hooks=merge_hooks(request.hooks, self.hooks),
  File "/usr/lib/python3/dist-packages/requests/", line 313, in prepare
    self.prepare_url(url, params)
  File "/usr/lib/python3/dist-packages/requests/", line 390, in prepare_url
    raise InvalidURL("Invalid URL %r: No host supplied" % url)
requests.exceptions.InvalidURL: Invalid URL 'https:///univention/saml/metadata': No host supplied