[systemd-devel] Failed to restart ntpd

[Kai Krakow]

Am Thu, 12 May 2016 11:51:13 +0200
schrieb Reindl Harald <h.reindl at thelounge.net>:

> Am 12.05.2016 um 11:46 schrieb liuxueping:
> > Before i restart ntpd,ntpd process was running:
> > ntp       3993  0.0  0.0   7404  4156 ?        Ss   10:21   0:00
> > /usr/sbin/ntpd -u ntp:ntp -g
> > root      3995  0.0  0.0   7404  2364 ?        S    10:21   0:00
> > /usr/sbin/ntpd -u ntp:ntp -g
> > so,it should be killed by systemctl and restart a new ntpd
> > process,but it failed,i want to know systemd how to judge that a
> > process is killed completed to start a new service.  
> 
> again: systemd monitors all processes part of a service
> systemctl itself does nothing, it just invokes commands
> 
> when you manually started a ntpd process systemd don't know it should
> be killed and *it should not* get killed just because "systemctl
> restart ntpd"
> 
> so when there is a ntpd process which is not listed in "systemctl 
> status" you or something has manually fired up that process - don't
> do that at all - and you need to kill it the same way

This situation may also happen, if shell scripts provide services and
try to do funny things like "su - $user" to switch to another user. This
creates a new session, PIDs started there seem not to be tracked by
systemd as part of the service. Reliable teardown by systemd is then
broken.

I had this problem with dccifd whose scripts try to be extraordinary
smart and reinvent the wheel.


-- 
Regards,
Kai

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