Bug 33968

Summary:	noVNC https connection error with Internet Explorer 11
Product:	UCS	Reporter:	Erik Damrose <damrose>
Component:	Virtualization - UVMM	Assignee:	Erik Damrose <damrose>
Status:	CLOSED FIXED	QA Contact:	Philipp Hahn <hahn>
Severity:	normal
Priority:	P5	CC:	best, gohmann, jmm, klaeser
Version:	UCS 3.2
Target Milestone:	UCS 3.2-1-errata
Hardware:	Other
OS:	Linux
See Also:	https://forge.univention.org/bugzilla/show_bug.cgi?id=33990 http://forge.univention.org/bugzilla/show_bug.cgi?id=34116
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Ticket number:		Bug group (optional):	Browser compatibility
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Description Erik Damrose

2014-01-22 13:31:14 CET

Internet Explorer 11 shows the following behaviour when accessing noVNC from uvmm's udm module: 

The first connection works fine, the user is asked to approve the certificate. 

If one logs out of UMC and closes the browser, then starts a new browser instance and navigates to the noVNC module, the connection is not possible, error 1015 is shown. No certificate approval page is shown.

Websockify shows the following traceback:

1: 10.200.29.51: new handler Process
1: handler exception: WSRequestHandler instance has no attribute 'last_code'
1: Traceback (most recent call last):
File "/usr/share/novnc/utils/websocket.py", line 782, in top_new_client
  self.client = self.do_handshake(startsock, address)
File "/usr/share/novnc/utils/websocket.py", line 714, in do_handshake
  if wsh.last_code == 101:
AttributeError: WSRequestHandler instance has no attribute 'last_code'

Comment 1 Alexander Kläser

2014-01-24 16:47:01 CET

Same problem (in a different context) has been reported in Bug 33990.

Comment 2 Erik Damrose

2014-04-09 14:53:21 CEST

Workaround is to press CTRL+F5 when the noVNC error is shown.

Comment 3 Erik Damrose

2014-04-11 16:33:52 CEST

The problem is fixed by adding HTML Metatags to forbid caching of vnc_auto.html. 

Internet Explorer loads the cached file and blocks when opening the secure websocket, instead of asking to validate the certificate.

If the html file is not cached, the user is asked to confirm the certificate. 

r49297 univention-novnc 0.4+0+20131014+git142aa45-4.5.201404111632
r49298 2014-04-11-univention-novnc.yaml

Comment 4 Philipp Hahn

2014-04-14 19:39:29 CEST

OK: r49297,r49298
FIXED: announce_errata -V 2014-04-11-univention-novnc.yaml (r49341)
OK: IE 11 Windows 7
OK: Iceweasel 24.4.0 Debian
OK: Chromium 33.0.1750.152 Debian 7.4 (256984)

Comment 5 Moritz Muehlenhoff

2014-04-16 16:12:14 CEST

http://errata.univention.de/ucs/3.2/91.html