[winswitch] Can't start xpra session

[Anthony Stone]

Antoine,

As recommended, I have set
start-via-proxy=no
in /etc/xpra/conf.d/60_server.conf
(and restarted the server)
and xpra now starts normally.

Many thanks for the prompt and helpful advice.

Anthony

On 30/08/18 18:13, Antoine Martin wrote:
> On 30/08/18 23:41, Anthony Stone wrote:
>> Antoine,
>>
>> Thanks for the suggestions. This is what happens:
> Please always keep the list CCed.
> 
>> On 30/08/18 04:22, Antoine Martin via shifter-users wrote:
>>> Directly on the server (ie: via ssh), try to start the session locally:
>>> xpra start :100 --start="gnome-terminal --window-with-profile=Blue"
>>
>> 17:22:05 $ xpra start :100 --start="gnome-terminal
>> --window-with-profile=Blue"
>> 2018-08-30 17:22:46,020 server failure: disconnected before the session
>> could be established
>> 2018-08-30 17:22:46,020 server requested disconnect: server error
>> (failed to start a new session)
>> Warning: cannot use the system proxy for 'start' subcommand,
>>  unknown general failure
>>  more information may be available in your system log
>>
>> The system log contains the following. This seems to be an
>> authentication failure, but I don't know how to fix it.
>>
>> Aug 30 17:22:32 whirligig systemd[1]: Started Session 2509 of user ajs1.
>> Aug 30 17:22:32 whirligig xpra[1192]: reenter password for
>> pam_mount:(pam_mount.c:477): warning: could not obtain password
>> interactively either
>> Aug 30 17:22:32 whirligig xpra[1192]: reenter password for
>> pam_mount:(pam_mount.c:477): warning: could not obtain password
>> interactively either
> Here is what I think is happening: when we start a proper pam session
> via root (this is what the "starting via proxy" does), we go through the
> pam session configuration.
> Your OS seems to include "pam_mount" in there, and that seems to want to
> ask for a password to do its job.
> I have no idea why that is, or why it isn't failing more gracefully.
> 
>> Aug 30 17:22:32 whirligig xpra[1192]: 2018-08-30 17:22:32,475 Error:
>> pam_open_session failed: 6
>> Aug 30 17:22:32 whirligig xpra[1192]: 2018-08-30 17:22:32,476
>> Permission denied
>> Aug 30 17:22:32 whirligig xpra[1192]: Entering daemon mode; any further
>> errors will be reported to:
>> Aug 30 17:22:32 whirligig xpra[1192]:   /run/user/1013/xpra/:100.log
>> Aug 30 17:22:46 whirligig xpra[1192]: Error: failed to start server
>> subprocess:
>> Aug 30 17:22:46 whirligig xpra[1192]:  failed to identify the new server
>> display!
> The easiest solution to this problem is to not use the proxy, set:
> start-via-proxy=no
> in your /etc/xpra/conf.d/60_server.conf
> 
> On this subject, there seems to be so many ways that distributions
> manage to configure (break) pam sessions, and logind's KillUserProcesses
> still defaults to "no" after all these years, so future versions will
> revert to not using the system wide proxy by default.
> Those who want the features that require it will have to re-enable it.
> 
> Cheers,
> Antoine
>