[systemd-devel] Antw: Re: Unexplainable unit restart ("Start request repeated too quickly")

[Ulrich Windl]

>>> Michael Chapman <mike at very.puzzling.org> schrieb am 03.06.2019 um 10:44 in
Nachricht <alpine.LFD.2.21.1906031830420.3180 at beren.home>:
> On Mon, 3 Jun 2019, Ulrich Windl wrote:
>> Hi!
>> 
>> When installing a test package, I noticed that one unit
>> (iotwatch-generator.service) triggered a restart for an unknown reason.
The
>> status is (note: no reason for restart shown):
>> 
>> # systemctl status iotwatch-generator.service -l
>> ● iotwatch-generator.service - I/O performance monitor instance generator
>>    Loaded: loaded (/usr/lib/systemd/system/iotwatch-generator.service;
>> enabled; vendor preset: disabled)
>>    Active: failed (Result: start-limit) since Mon 2019-06-03 09:41:18
CEST;
>> 5min ago
>>      Docs: man:iotwatch-generator(8)
>>            man:iotwatch at .service(8)
>>   Process: 29133 ExecStart=/usr/lib/iotwatch/iotwatch-generator
>> /run/systemd/system (code=exited, status=0/SUCCESS)
>>  Main PID: 29133 (code=exited, status=0/SUCCESS)
>> 
>> Jun 03 09:41:18 v04 systemd[1]: Starting I/O performance monitor instance
>> generator...
>> Jun 03 09:41:18 v04 systemd[1]: Started I/O performance monitor instance
>> generator.
>> Jun 03 09:41:22 v04 systemd[1]: iotwatch-generator.service: Start request
>> repeated too quickly.
>> Jun 03 09:41:22 v04 systemd[1]: Failed to start I/O performance monitor
>> instance generator.
>> Jun 03 09:41:22 v04 systemd[1]: iotwatch-generator.service: Unit entered
>> failed state.
>> Jun 03 09:41:22 v04 systemd[1]: iotwatch-generator.service: Failed with 
> result
>> 'start-limit'.
>> 
>> So there was a successful start, but then some spurious restart. Why?
> 
> It'd probably be easier if you supplied us with these units' 
> configurations. My distribution does not ship iotwatch at .service or 
> iotwatch-generator.service units.

Hi!

The generator unit is:
[Unit]
Description=I/O performance monitor instance generator
Documentation=man:iotwatch-generator(8) man:iotwatch at .service(8)
Wants=nss-user-lookup.target time-sync.target paths.target
After=nss-user-lookup.target time-sync.target paths.target
ConditionPathExists=/etc/iotwatch.conf
Conflicts=shutdown.target

[Service]
Type=oneshot
ExecStart=/usr/lib/iotwatch/iotwatch-generator /run/systemd/system
TimeoutStartSec=10
RestartPreventExitStatus=2 3 4 5
StartLimitBurst=1

[Install]
WantedBy=default.target iotwatch.target


The iotwatch.target is:
[Unit]
Description=iotwatch I/O performance monitor
Documentation=man:iotwatch at .service(8) man:iotwatch-generator(8)
After=nss-lookup.target time-sync.target paths.target
Wants=iotwatch at NFS1.service iotwatch at NFS2.service iotwatch at LOC1.service 

[Install]
WantedBy=default.target

and the instance services look like:
# automatically generated by /usr/lib/iotwatch/iotwatch-generator

[Unit]
Description=iotwatch I/O performance monitor instance "LOC1"
Documentation=man:iotwatch(1) man:iotwatch at .service(8)
SourcePath=/etc/iotwatch.conf
PartOf=iotwatch.target
Requires=iotwatch-generator.service
Wants=nss-user-lookup.target time-sync.target paths.target
After=iotwatch-generator.service
After=nss-user-lookup.target time-sync.target paths.target
ConditionPathExists=/etc/passwd
Conflicts=shutdown.target

[Service]
Type=forking
RuntimeDirectory=iotwatch-LOC1
WorkingDirectory=/var/run/iotwatch-LOC1
ExecStartPre=/bin/sh -c '...'
ExecStart=@/var/run/iotwatch-LOC1/iotwatch-LOC1 iotwatch-LOC1 -l ...
/etc/passwd
ExecStartPost=/usr/bin/sleep 0.2
TimeoutStartSec=10
ExecStop=/var/run/iotwatch-LOC1/iotwatch-LOC1 -l ...
#SyslogIdentifier=%p-LOC1
TimeoutStopSec=30
PIDFile=/var/run/iotwatch-LOC1/iotwatch-LOC1.pid
Restart=always
RestartSec=10s
RestartPreventExitStatus=1
StartLimitBurst=1

[Install]
WantedBy=iotwatch.target

> 
> It might also be good to know the RequiredBy, WantedBy, TriggeredBy, 
> RequisiteOf and PartOf properties of this iotwatch-generator.service (see 
> `systemctl show iotwatch-generator.service`), since they're possible ways 
> in which the service may be implicitly started or restarted.

Yes, but I'm missing a log message that explains what happened.

Regards,
Ulrich Windl