Can not generate diagnostic snapshot

[Kyrylo Romanenko]

Steps:
1. Deploy cluster.
2. Navigate to http://<fuel ip>:8000/#support
3. Click on Generate Diagnostic Snapshot.

Got text "exit code: 1 stderr:" instead of the link to the diagnostic snapshot.

Also, can not generate snapshot from CLI:
[root@nailgun ~]# fuel snapshot
Generating dump...
Traceback (most recent call last):
  File "/usr/bin/fuel", line 10, in <module>
    sys.exit(main())
  File "/usr/lib/python2.7/site-packages/fuelclient/cli/error.py", line 115, in wrapper
    return func(*args, **kwargs)
  File "/usr/lib/python2.7/site-packages/fuelclient/cli/parser.py", line 266, in main
    parser.parse()
  File "/usr/lib/python2.7/site-packages/fuelclient/cli/parser.py", line 143, in parse
    actions[parsed_params.action].action_func(parsed_params)
  File "/usr/lib/python2.7/site-packages/fuelclient/cli/actions/base.py", line 62, in action_func
    method(params)
  File "/usr/lib/python2.7/site-packages/fuelclient/cli/actions/snapshot.py", line 68, in get_snapshot
    directory=params.dir
  File "/usr/lib/python2.7/site-packages/fuelclient/cli/formatting.py", line 118, in download_snapshot_with_progress_bar
    download_handle = urllib.request.urlopen(request)
  File "/usr/lib64/python2.7/urllib2.py", line 127, in urlopen
    return _opener.open(url, data, timeout)
  File "/usr/lib64/python2.7/urllib2.py", line 404, in open
    response = self._open(req, data)
  File "/usr/lib64/python2.7/urllib2.py", line 422, in _open
    '_open', req)
  File "/usr/lib64/python2.7/urllib2.py", line 382, in _call_chain
    result = func(*args)
  File "/usr/lib64/python2.7/urllib2.py", line 1216, in http_open
    return self.do_open(httplib.HTTPConnection, req)
  File "/usr/lib64/python2.7/urllib2.py", line 1186, in do_open
    raise URLError(err)
urllib2.URLError: <urlopen error [Errno -2] Name or service not known>

VERSION:
  feature_groups:
    - mirantis
  production: "docker"
  release: "8.0"
  api: "1.0"
  build_number: "344"
  build_id: "344"
  fuel-nailgun_sha: "bad4d014df29beaf3708f1a050e808d20542b878"
  python-fuelclient_sha: "4f234669cfe88a9406f4e438b1e1f74f1ef484a5"
  fuel-agent_sha: "1d3a2b8d9e8961ebcdfa5db55e2e809f7dd404a8"
  fuel-nailgun-agent_sha: "92ebd5ade6fab60897761bfa084aefc320bff246"
  astute_sha: "c7ca63a49216744e0bfdfff5cb527556aad2e2a5"
  fuel-library_sha: "9cbb065084fda775270cc923525de711a5586300"
  fuel-ostf_sha: "d8cbc4f65361e034193479b19f84747d1c33894e"
  fuel-mirror_sha: "d15edd2128b9a4644f1db8089b0ecdf7954a2e57"
  fuelmenu_sha: "1e99db70b255da8eeddb2c4e113ff4860a968b67"
  shotgun_sha: "bf79f1ac08a256160f2835a71808ec4f8d2bbf9e"
  network-checker_sha: "9f0ba4577915ce1e77f5dc9c639a5ef66ca45896"
  fuel-upgrade_sha: "616a7490ec7199f69759e97e42f9b97dfc87e85b"
  fuelmain_sha: "07d5f1c3e1b352cb713852a3a96022ddb8fe2676"