Failed to add PIDs to scope's control group: Permission denied

[Ramiro]

I am on the server side, an Ubuntu 18.04, with xpra version 2.1.3.

When I try:

rmagno@r2d2:~$ PATH="/usr/lib/xorg:$PATH" xpra start --bind-tcp=0.0.0.0:14500 --html=on --start=xterm

I get:

using systemd-run to wrap 'start' server command
'systemd-run' '--description' 'xpra-start' '--scope' '--user' '/usr/bin/xpra' 'start' '--bind-tcp=0.0.0.0:14500' '--html=on' '--start=xterm' '--systemd-run=no'
Job for run-rc4c6fd6f0a8445b08d9bfb1da717308c.scope failed.
See "systemctl status run-rc4c6fd6f0a8445b08d9bfb1da717308c.scope" and "journalctl -xe" for details.

then journalctl -xe shows me:

Nov 16 07:35:28 r2d2 systemd[26686]: run-rb32e0e35376249e1b0d77b784c1beffb.scope: Failed to add PIDs to scope's control group: Permission denied
Nov 16 07:35:28 r2d2 systemd[26686]: run-rb32e0e35376249e1b0d77b784c1beffb.scope: Failed with result 'resources'.
Nov 16 07:35:28 r2d2 systemd[26686]: Failed to start xpra-start.

[Antoine Martin]

Is this from an SSH session? This works fine from a regular terminal in my Ubuntu 18.04 VM.

That said, I'm using a supported version (2.4.1) and you are not (2.1.3).
Please do not use the version provided by the Ubuntu repositories which is fundamentally broken and insecure (more details here: wiki/Packaging/DistributionPackages)

[Ramiro]

Could you please instruct me on how to install version 2.4.1 under Ubuntu 18.04?

And yes, I am trying to run that command from an SSH session.

BTW: How to check xpra version?

[Ramiro]

connect.html error msg

[Antoine Martin]

Could you please instruct me on how to install version 2.4.1 under Ubuntu 18.04?

See wiki/Download.

And yes, I am trying to run that command from an SSH session.

This can cause problems under some circumstances.
If you still encounter issues after upgrading, start your sessions first, then connect over ssh - rather than doing all in one.

BTW: How to check xpra version?

xpra --version