Hi, all When I access the REST API like this ==================================== import urllib2 theurl = 'http://9.181.129.112:8080/api' username = 'admin@internal' password = 'abcd1234' # a great password passman = urllib2.HTTPPasswordMgrWithDefaultRealm() passman.add_password('ENGINE', theurl, username, password) authhandler = urllib2.HTTPBasicAuthHandler(passman) opener = urllib2.build_opener(authhandler) urllib2.install_opener(opener) pagehandle = urllib2.urlopen(theurl) ========================================= urlopen failed. then We do that another way like this, it is ok ======================================== import urllib2 import sys import re import base64 import xml.etree.ElementTree as etree username='admin@internal' password='abcd1234' request = urllib2.Request("http://9.181.129.112:8080/api") base64string = base64.encodestring('%s:%s' % (username, password)).replace('\n', '') request.add_header("Authorization", "Basic %s" % base64string) result = urllib2.urlopen(request) by catching the packets transfered, we found the response from ovirt-engine server as below for failing case: ================================================================ GET /api HTTP/1.1 Accept-Encoding: identity Host: 9.181.129.112:8080 Connection: close User-Agent: Python-urllib/2.7 HTTP/1.1 401 Unauthorized Server: Apache-Coyote/1.1 WWW-Authenticate: Basic realm = "ENGINE" Content-Type: text/html;charset=utf-8 Content-Length: 956 Date: Fri, 04 May 2012 09:18:06 GMT Connection: close Is there anything wrong for oVirt-engine? Thanks!