Cannot start xpra shadow with 226**

[totaam]

Issue migrated from trac ticket # 2296

component: server | priority: minor | resolution: fixed

2019-05-13 10:40:19: stdedos created the issue

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py3-x64-r22647 on Ubuntu 16.04.5 LTS Server and
Xpra-Python3_2.5.2-r22633 on Win10 client

From the Windows 10 client:

\xpra-clients\Xpra-Python3_2.5.2-[r22633](../commit/5b3fa375a2ab316d29211169a4f0ca5873437690)\xpra_cmd" shadow ssh://user@ip/0  --opengl=no --desktop-scaling=0.75 --webcam=no --speaker=off --microphone=off --exit-with-client=no

2019-05-13 12:36:32,206 Xpra GTK3 client version 2.5.2-[r22633](../commit/5b3fa375a2ab316d29211169a4f0ca5873437690) 32-bit
2019-05-13 12:36:32,209  running on Microsoft Windows 10
2019-05-13 12:36:32,749 GStreamer version 1.14.4 for Python 3.7.3 32-bit
2019-05-13 12:36:33,110  keyboard settings: layout=us
2019-05-13 12:36:33,112  desktop size is 1600x900 with 1 screen:
2019-05-13 12:36:33,112   Default (423x238 mm - DPI: 96x96) workarea: 1600x860
2019-05-13 12:36:33,112     (Standard monitor types) Generic PnP Monitor (309x174 mm - DPI: 131x131)
2019-05-13 12:36:33,112  downscaled to 75%, virtual screen size: 2133x1200
2019-05-13 12:36:33,113   Default (423x238 mm - DPI: 128x128) workarea: 2133x1147
2019-05-13 12:36:33,113     (Standard monitor types) Generic PnP Monitor (309x174 mm - DPI: 175x175)
2019-05-13 12:36:42,230 Error: failed to receive anything, not an xpra server?
2019-05-13 12:36:42,232   could also be the wrong protocol, username, password or port
2019-05-13 12:36:42,233   or the session was not found
2019-05-13 12:36:42,233 Connection lost

From an existing xpra-start-gnome-terminal (:2):

user@host [2019-05-13 12:24:45]:/run/user/1000/xpra$ env -i bash -c ' . /run/user/1000/dbus-session; xpra shadow :0'
xpra for python 2.7 is not installed
 retrying with python3
using systemd-run to wrap 'shadow' server command
'systemd-run' '--description' 'xpra-shadow' '--scope' '--user' 'python3' '/usr/bin/xpra' 'shadow' ':0' '--systemd-run=no'
Failed to create bus connection: No such file or directory
user@host [2019-05-13 12:25:07]:/run/user/1000/xpra$ xpra shadow :0
xpra for python 2.7 is not installed
 retrying with python3
using systemd-run to wrap 'shadow' server command
'systemd-run' '--description' 'xpra-shadow' '--scope' '--user' 'python3' '/usr/bin/xpra' 'shadow' ':0' '--systemd-run=no'
Failed to create bus connection: No such file or directory

No logs get generated on the server to attach.

[totaam]

2019-05-13 10:49:46: stdedos commented

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(Basic xpra start :10 works)

[totaam]

2019-05-13 11:58:50: antoine changed owner from antoine to stdedos

[totaam]

2019-05-13 11:58:50: antoine commented

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Have you tried with the python2 builds?

[totaam]

2019-05-15 08:22:27: stdedos commented

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python2-xpra seems to work okay (just pulled it)

[totaam]

2019-05-15 13:00:20: antoine changed priority from major to minor

[totaam]

2019-05-15 13:00:20: antoine changed status from new to assigned

[totaam]

2019-05-15 13:00:20: antoine changed owner from stdedos to antoine

[totaam]

2019-05-15 13:00:20: antoine commented

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The ssh command ends up running:

$XDG_RUNTIME_DIR/xpra/run-xpra _proxy_shadow_start

And since the default python2 version is not installed, it re-execs the script with python3 via os.execvpe.

Strangely, this fails with: failed to indentify the new server display.

[totaam]

2019-05-15 16:34:04: antoine changed status from assigned to new

[totaam]

2019-05-15 16:34:04: antoine changed owner from antoine to stdedos

[totaam]

2019-05-15 16:34:04: antoine commented

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This should be fixed in r22716, but unfortunately we cannot fix a script that has already been generated: an ssh connection will just use it as it is.
So this may not fix things until you wipe $XDG_RUNTIME_DIR (on some platforms, a reboot might do this)
Or you could edit $XDG_RUNTIME_DIR/xpra/run-xpra by hand and just remove XPRA_ALT_PYTHON_RETRY from there.

[totaam]

2019-05-16 13:20:14: stdedos commented

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Replying to [comment:5 Antoine Martin]:

This should be fixed in r22716, but unfortunately we cannot fix a script that has already been generated: an ssh connection will just use it as it is.
So this may not fix things until you wipe $XDG_RUNTIME_DIR (on some platforms, a reboot might do this)
Or you could edit $XDG_RUNTIME_DIR/xpra/run-xpra by hand and just remove XPRA_ALT_PYTHON_RETRY from there.

I did that:

user@server [2019-05-16 15:18:27]:/run/user/1000/xpra$ grep XPRA_ALT_PYTHON_RETRY /run/user/1000/xpra/run-xpra
user@server [2019-05-16 15:18:58]:/run/user/1000/xpra$ 

Still not working (haven't updated either).

I needed to re-install python2-xpra for it to work

[totaam]

2019-06-13 12:42:19: antoine commented

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Not sure how I had missed that, but running run-xpra _proxy_shadow_start was erroring out with python3, r22926 fixes that.

(there's still a segfault on server exit - but that's a different thing)

@stdedos: does that fix things for you? (the trivial patch can be applied by hand to the server)

[totaam]

2019-06-13 13:01:10: antoine commented

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new ticket for the shadow segfault with python3 on Ubuntu 16.04: #2328

[totaam]

2019-06-19 22:23:21: stdedos commented

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Replying to [comment:7 Antoine Martin]:

Not sure how I had missed that, but running run-xpra _proxy_shadow_start was erroring out with python3, r22926 fixes that.

(there's still a segfault on server exit - but that's a different thing)

@stdedos: does that fix things for you? (the trivial patch can be applied by hand to the server)

I have had applied the patch, and I have installed the latest xenial beta (as of Wed morning) for #2338. So, I guess things are working.

I don't remember, though, if I have removed the py2 package; I need to check that tomorrow * --> No, I haven't. Need to try again on Monday. :/*

[totaam]

2019-06-24 12:36:29: stdedos changed status from new to closed

[totaam]

2019-06-24 12:36:29: stdedos set resolution to fixed

[totaam]

2019-06-24 12:36:29: stdedos commented

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The proposed solution does not work:

~$  grep -i 'XPRA_ALT_PYTHON_RETRY' $XDG_RUNTIME_DIR/xpra/run-xpra
~$ 

but just removing the file seems to be fine