After an evaluation, GNOME has moved from Bugzilla to GitLab. Learn more about GitLab.
No new issues can be reported in GNOME Bugzilla anymore.
To report an issue in a GNOME project, go to GNOME GitLab.
Do not go to GNOME Gitlab for: Bluefish, Doxygen, GnuCash, GStreamer, java-gnome, LDTP, NetworkManager, Tomboy.
Bug 385451 - XDMCP doesn't work with ipv6
XDMCP doesn't work with ipv6
Status: RESOLVED FIXED
Product: gdm
Classification: Core
Component: general
2.17.x
Other All
: Normal normal
: ---
Assigned To: GDM maintainers
GDM maintainers
Depends on:
Blocks:
 
 
Reported: 2006-12-13 13:46 UTC by Laurent Bigonville
Modified: 2007-08-10 09:43 UTC
See Also:
GNOME target: ---
GNOME version: 2.17/2.18


Description Laurent Bigonville 2006-12-13 13:46:56 UTC 
Please describe the problem:
I cannot connect to an another host with XDMCP if the 'server' has an ipv6 address. I have to blacklist the ipv6 module on the server to make it works.

The ip shown in an ipv4 one, but according to tcpdump the connection is made in ipv6.

In the client logs I get "gdm[9278]: gdm_slave_xioerror_handler : erreur X fatale - Redémarrage de :20"

Steps to reproduce:
1. Select XDMCP chooser
2. Select an host with ipv6 enabled (the address shown is an ipv4 one)
3. Enter Login and Password.
4. Try to login.

Actual results:
GDM restart

Expected results:
Get my session

Does this happen every time?
yep, only if the 'server' has an ipv6 address

Other information:
Distro: Ubuntu feisty, but same problem with previous versions.
LP: https://launchpad.net/distros/ubuntu/+source/gdm/+bug/75254
Comment 1 Laurent Bigonville 2007-01-03 10:22:32 UTC 
both server and client gdm were compiled without ipv6 support. The negotiation was made in ipv4 and the export display in ipv6. The problem comes from that.

If both client and server are compiled with ipv6 support, no problem any more. When connecting to the xdmcp port in v4 the export is made in v4 and if connection to xdmcp port is made in v6, export is made in v6.

The only issue that remains is the ip address shown on the chooser, if the connection will be made in v6, the ipv4 address is shown.
Comment 2 Laurent Bigonville 2007-01-03 10:29:06 UTC 
Edit: It seems that the client gdm event compiled with ipv6 support always choose to connect iv v4 when server selected in chooser
Comment 3 Brian Cameron 2007-02-05 04:31:39 UTC 
Note a fix just went into GDM SVN head and 2.16 branch where an assertion was caused when gdm_xdmcp_send_forward_query was called for IPv6, instead of calling the IPv6 function.  Might be worth testing to see if GDM from SVN head fixes this problem.

Also note bug #164628 might be related.  There is a patch in that bug.  Could you test and see if that fixes the problem?
Comment 4 Brian Cameron 2007-08-09 23:13:16 UTC 
Can this be tested with 2.19?  If not, I will assume that the many IPv6 fixes we've made since 2.17 have probably fixed this problem.
Comment 5 Sebastien Bacher 2007-08-10 09:43:37 UTC 
distribution comment "As I said on the gnome bugzilla compiling both server and client with --enable-ipv6=yes solve the problem."

I'm closing the bug