[winswitch] xpra: unable to start sessions

Fri May 11 16:05:21 BST 2018

Hello Antoine,

I'm having a lot of trouble trying to start xpra sessions over an ssh
connection. The attached file gives some details. This has only started
to be a problem recently, I think since xpra 2.3 was installed on the
server. Is there an incompatibility between v2.2.6 and v2.3?

Any suggestions welcome.

Thanks,
Anthony
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Unsuccesful attempts to start xpra sessions. Until recently I have been able
to connect without any trouble using 
 $ xpra start ssh/whirligig/100 --start=gnome-terminal &

Recent attempts have been unsuccessful. After restarting both machines,
I attempted twice to start an xpra session on whirligig (the server) from
redwing (the client), using the command
 $ xpra start ssh/whirligig --start=gnome-terminal &
This failed:

Error: displayfd failed
 did not provide a display number using displayfd
xpra initialization error:
 failed to identify the new server display!
2018-05-11 15:43:26,658 Error: failed to receive anything, not an xpra server?
2018-05-11 15:43:26,658   could also be the wrong protocol, username, password or port
2018-05-11 15:43:26,658 Connection lost

If I used my usual command:
 $ xpra start ssh/whirligig/100 --start=gnome-terminal &
This too failed:

cannot find live server for display :100
2018-05-11 15:35:39,845 Error: failed to receive anything, not an xpra server?
2018-05-11 15:35:39,845   could also be the wrong protocol, username, password or port
2018-05-11 15:35:39,846 Connection lost

In an ssh session on the server (whirligig) after the first two attempts,
I found the following:

 $ xpra list
Found the following xpra sessions:
/run/user/1013/xpra:
	LIVE session at :2
	LIVE session at :4
/home/ajs1/.xpra:
	LIVE session at :2
	LIVE session at :4
/run/xpra:
	LIVE session at :2
	LIVE session at :4

 $ ps -ef | grep xpra
ajs1     27502     1  0 May10 ?        00:00:02 /usr/bin/python /usr/bin/xpra start :100 --chdir=/home/ajs1 --video-decoders=all --packet-encoders=rencode, bencode, yaml --start=gnome-terminal --start-env=#avoid Ubuntu's global menu, which is a mess and cannot be forwarded: --start-env=UBUNTU_MENUPROXY= --start-env=QT_X11_NO_NATIVE_MENUBAR=1 --start-env=#fix for MainSoft's MainWin buggy window management: --start-env=MWNOCAPTURE=true --start-env=MWNO_RIT=true --start-env=MWWM=allwm --start-env=#force GTK3 applications to use X11 so we can intercept them: --start-env=GDK_BACKEND=x11 --env=XPRA_PROXY_START_UUID=07e25f9c7a9144c7b5ddb5c0b44c951c --video-encoders=all --bind=auto --encodings=h264,vp9,vp8,mpeg4,mpeg4+mp4,h264+mp4,vp8+webm,vp9+webm,png,webp,rgb,rgb24,rgb32,jpeg,h265,jpeg2000 --compressors=lz4, lzo, zlib --csc-modules=all --attach=no --start-via-proxy=no --daemon=yes --systemd-run=no --uid=1013 --gid=1013
ajs1     27597 27502  0 May10 ?        00:00:00 pulseaudio --start -n --daemonize=false --system=false --exit-idle-time=-1 --load=module-suspend-on-idle --load=module-null-sink sink_name="Xpra-Speaker" sink_properties=device.description="Xpra\ Speaker" --load=module-null-sink sink_name="Xpra-Microphone" sink_properties=device.description="Xpra\ Microphone" --load=module-native-protocol-unix socket=/run/user/1013/xpra/pulse-:100/pulse/native --load=module-dbus-protocol --load=module-x11-publish --log-level=2 --log-target=stderr
root     29136     1  0 06:41 ?        00:00:00 /usr/bin/python /usr/bin/xpra proxy :14500 --daemon=no --bind-tcp=0.0.0.0:14500 --tcp-auth=sys --ssl-cert=/etc/xpra/ssl-cert.pem --ssl=on --bind=/run/xpra/system --auth=peercred --socket-dirs=/run/xpra --socket-permissions=666 --log-dir=/var/log --pidfile=/run/xpra.pid --debug=
ajs1     30694     1  0 15:15 ?        00:00:00 /usr/bin/python /usr/bin/xpra start --start=gnome-terminal --encodings=h264,vp9,vp8,mpeg4,mpeg4+mp4,h264+mp4,vp8+webm,vp9+webm,png,webp,rgb,rgb24,rgb32,jpeg,h265,jpeg2000 --env=XPRA_PROXY_START_UUID=7d0122c63e634307a5bf09e0bb141fa6 --daemon=yes --systemd-run=no --displayfd=5 --start-via-proxy=no
ajs1     30897 30694  0 15:16 ?        00:00:00 pulseaudio --start -n --daemonize=false --system=false --exit-idle-time=-1 --load=module-suspend-on-idle --load=module-null-sink sink_name="Xpra-Speaker" sink_properties=device.description="Xpra\ Speaker" --load=module-null-sink sink_name="Xpra-Microphone" sink_properties=device.description="Xpra\ Microphone" --load=module-native-protocol-unix socket=/run/user/1013/xpra/pulse-:2/pulse/native --load=module-dbus-protocol --load=module-x11-publish --log-level=2 --log-target=stderr
ajs1     31634     1  0 15:16 ?        00:00:00 /usr/bin/python /usr/bin/xpra start --start=gnome-terminal --encodings=h264,vp9,vp8,mpeg4,mpeg4+mp4,h264+mp4,vp8+webm,vp9+webm,png,webp,rgb,rgb24,rgb32,jpeg,h265,jpeg2000 --env=XPRA_PROXY_START_UUID=8a3978040530489487867538e2cbe44e --daemon=yes --systemd-run=no --displayfd=5 --start-via-proxy=no
ajs1     31678 31634  0 15:16 ?        00:00:00 pulseaudio --start -n --daemonize=false --system=false --exit-idle-time=-1 --load=module-suspend-on-idle --load=module-null-sink sink_name="Xpra-Speaker" sink_properties=device.description="Xpra\ Speaker" --load=module-null-sink sink_name="Xpra-Microphone" sink_properties=device.description="Xpra\ Microphone" --load=module-native-protocol-unix socket=/run/user/1013/xpra/pulse-:4/pulse/native --load=module-dbus-protocol --load=module-x11-publish --log-level=2 --log-target=stderr
ajs1     32472 32392  0 15:23 pts/10   00:00:00 grep xpra

but attempts to attach to these also failed.

$ uname -a
Linux whirligig 4.4.0-124-generic #148-Ubuntu SMP Wed May 2 13:00:18 UTC 2018 x86_64 x86_64 x86_64 GNU/Linux
 $ xpra --version
xpra v2.3-r19255

On the client (redwing):

 $ uname -a
Linux Redwing 4.4.0-124-generic #148-Ubuntu SMP Wed May 2 13:00:18 UTC 2018 x86_64 x86_64 x86_64 GNU/Linux
 $ xpra --version
xpra v2.2.6-r18968

Trying to start a session directly on the server, as suggested in the tutorial:

 $ xpra start :100 --start-child=gnome-terminal &
[1] 570
 $ 2018-05-11 15:34:46,732 server failure: disconnected before the session could be established
2018-05-11 15:34:46,732 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
Entering daemon mode; any further errors will be reported to:
  /run/user/1013/xpra/:100.log