[systemd-devel] : How to modify systemd so that the NTP function is disabled when systemd is first started?

[Michał Zegan]

As I said, there are symlinks in /etc/systemd/system/*.target.wants that
allows disabling services like this one from starting. It is enough to
remove the one for systemd-timesync.service from multi-user.target.wants
directory. If you can do things via some config files you should also be
able to do this

W dniu 23.04.2020 o 04:14, www pisze:
> 
> hi Michal and Kevin,
> 
> We applied systemd to embedded Linux, so we often need to update/flash
> the whole system.  When we select disable *time synchronization*
> function, the embedded system will use the time itself. After we update
> the system and restart it, we need the *time synchronization* function
> is disabled. During the whole startup process, there is no automatic
> time synchronization, and *the previous time is used*. Because automatic
> time synchronization may change its original time. （*Because the time
> of the system itself may be different from that of NTP time.*） 
> 
> There is a *timesyncd.conf* file under the system，can the system
> automatically turn off the time synchronization function by modifying
> this file? 
> In this way, when updating, I can save this file to solve this problem.
> 
> 
> thanks,
> Byron
> 
> 
> 
> 
> At 2020-04-17 19:44:48, "Michał Zegan" <webczat_200 at poczta.onet.pl> wrote:
>>I am not quite sure what you mean, but... generally these are symlinks
>>in /etc/systemd/system/multi-user.target.wants/ so you could delete them
>>manually if your intention is to make the actual os image with this
>>disabled from the start...
>>
>>W dniu 17.04.2020 o 12:10, www pisze:
>>> 
>>> I mean that this configuration can be preserved, even after I update the
>>> system, this function can be saved.
>>> 
>>> thanks，
>>> Byron
>>> 
>>> 
>>> 
>>> 
>>> At 2020-04-17 18:06:15, "Kevin P. Fleming" <kevin at km6g.us> wrote:
>>>>Both of those changes will stop the service from being started, even
>>>>when the system is rebooted. You don't need to run these commands
>>>>every time, running them one time will change the system configuration
>>>>and the service will no longer be started.
>>>>
>>>>On Fri, Apr 17, 2020 at 2:52 AM www <ouyangxuan10 at 163.com> wrote:
>>>>>
>>>>> hi Kevin ,
>>>>>
>>>>> Thank you very much for you help. But how can I save this way of closing time synchronization by command after system boot up? After I update the system, the first time I start it, time synchronization is still enabled by default. It's not appropriate if I close it alone every time. So when I need it start every time, this function is off.
>>>>>
>>>>>
>>>>> thanks,
>>>>> Byron
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>> At 2020-04-16 18:28:30, "Kevin P. Fleming" <kevin at km6g.us> wrote:
>>>>> >There is no need to modify systemd.
>>>>> >
>>>>> >$ systemctl disable systemd-timesyncd
>>>>> >
>>>>> >That command will stop the systemd-timesyncd service from being
>>>>> >started. It may also be necessary to mask it:
>>>>> >
>>>>> >$ systemctl mask systemd-timesyncd
>>>>> >
>>>>> >On Thu, Apr 16, 2020 at 6:22 AM www <ouyangxuan10 at 163.com> wrote:
>>>>> >>
>>>>> >> Dear all，
>>>>> >>
>>>>> >> I want to ask a question，How to modify systemd so that the NTP function is disabled when systemd is first started?
>>>>> >>
>>>>> >>  The default state of systend is to synchronize time from NTP. We can use timedatectl command to disable NTP synchronize time. But if I flash the system, the NTP  synchronize time function will auto enable.  so I want modify the systemd and disable NTP synchronize time in default state.
>>>>> >>
>>>>> >> thanks,
>>>>> >> Byron
>>>>> >>
>>>>> >>
>>>>> >>
>>>>> >>
>>>>> >> _______________________________________________
>>>>> >> systemd-devel mailing list
>>>>> >> systemd-devel at lists.freedesktop.org
>>>>> >> https://lists.freedesktop.org/mailman/listinfo/systemd-devel
>>>>>
>>>>>
>>>>>
>>>>>
>>> 
>>> 
>>> 
>>>  
>>> 
>>> 
>>> _______________________________________________
>>> systemd-devel mailing list
>>> systemd-devel at lists.freedesktop.org
>>> https://lists.freedesktop.org/mailman/listinfo/systemd-devel
>>> 
>>
> 
> 
> 
>  
> 

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