Hi, The hint with the 'KillUserProcesses' setting was exactly what I needed. We indeed use a distro which is setting this to 'no' and this caused all my issues. When I set it to yes then the "login" done by the service seems to be correctly cleaned up by loginctl. This is exactly the clean solution I was looking for.
Thanks and Kind Regards, Michael -----Original Message----- From: Lennart Poettering <lenn...@poettering.net> Sent: Thursday, February 6, 2025 4:01 PM To: Dluhosch, Michael <michael.dluho...@airbus.com> Cc: systemd-devel@lists.freedesktop.org Subject: Re: [systemd-devel] How to stop child cgroup caused by PAMName= On Do, 06.02.25 08:25, Dluhosch, Michael (michael.dluho...@airbus.com) wrote: > Hello, > > > I want a service which executes 'startFoo.sh' exactly like a user 'Foo' would > experience it. This is my current approach: > > [Service] > ExecStart=/usr/bin/startFoo.sh > > User=Foo > > PAMName=login > > > And it seems to work just fine. But I can't figure out how to stop > this service and all of its childs in a clean way. According to the > systemd.exec documentation this service will start a 'session scope' > CGroup but it does not mention how to stop this when the service > stops. Well, the whole session concept is about disconnecting lifecycles of the login manager and the sessions they spawn a bit (i.e. that the sessions can be killed independently of the session manager and can be tracked separately from it). > So far I found this workaround: > > I add a > > ExecStop=/usr/bin/stopFoo.sh > > to the main service which does that: > > #!/bin/bash > systemctl stop $(systemctl status $(pidof > <anyProcessNameInsideTheChildCGroup>) | grep user.*slice | grep -o > session.*scope) > > Is there a clean solution to accomplish something like this? Well, a service can register as many sessions as it wants, simultaneously or serially, everything is allowed, hence there is no direct 1:1 connection between service and scope and what you are asking for is not necessarily available. I guess you could theoretically bind the lifetime of your session object to the lifetime of the allocating service via BindsTo= but we currently have no way to request that in a friendly way. That said, why is this even an issue? note that logind tracks the primary process of a session as its "leader" and binds the session's lifetime to that leader process lifetime. Except of course you are using some distro that turns KillUserProcesses= off, which disables this logic for compat with legacy. Lennart -- Lennart Poettering, Berlin The information in this e-mail is confidential. The contents may not be disclosed or used by anyone other than the addressee. Access to this e-mail by anyone else is unauthorised. If you are not the intended recipient, please notify Airbus immediately and delete this e-mail. Airbus cannot accept any responsibility for the accuracy or completeness of this e-mail as it has been sent over public networks. If you have any concerns over the content of this message or its Accuracy or Integrity, please contact Airbus immediately. All outgoing e-mails from Airbus are checked using regularly updated virus scanning software but you should take whatever measures you deem to be appropriate to ensure that this message and any attachments are virus free.
