[systemd-devel] is systemd killing dhclient?,

[Ido Barkan]

Thanks a lot!

I have chased that for a long time.
As I understand this is a feature and not a bug, IMO this behavior is very surprising.
If a process was killed during ExecStartPre I would expect the starting of the service unit
to fail (not happen). This is because something obviously went wrong during the preparation 
for the service.
Killing the forking process and launching the service is simply a cause for bugs and confusion.
For the very least I would expect an info level clear warning.

Thanks again for your help.
Ido

----- Original Message -----
From: "Lennart Poettering" <lennart at poettering.net>
To: "Ido Barkan" <ibarkan at redhat.com>
Cc: systemd-devel at lists.freedesktop.org
Sent: Monday, March 9, 2015 7:03:41 PM
Subject: Re: [systemd-devel] is systemd killing dhclient?

On Mon, 09.03.15 09:14, Ido Barkan (ibarkan at redhat.com) wrote:

> Hi All,
> 
> I am a VDSM developer at Ovirt project.
> 
> VDSM is a daemon which is run as a systemd unit and manages a RHEV hypervisor.
> During it's start up, under ExecStartPre the unit runs an initialization script, that calls 
> a part of VDSM in order to configure networking on the host. During the network initialization
> 'ifup' is called for interfaces with DHCP defined as their boot protocol. dhclient then runs, 
> assigns an IP address to the interface and .... gets killed!

Yes, this is intended behaviour. ExecStartPre= is for running
preparatory code, not for forking off long-running
processes. 

I have now added a note about this the man page, since this wasn't
documented so far.

Lennart

-- 
Lennart Poettering, Red Hat