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why does /etc/conf.d/ntpd has "-g" ?
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toralf
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PostPosted: Sat Jun 04, 2016 9:26 pm    Post subject: why does /etc/conf.d/ntpd has "-g" ? Reply with quote

I'd assume that /etc/init.d/ntp-client is used to set a time during boot and therefore ntpd shouldn't face any big time jump values, or ?
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Syl20
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PostPosted: Mon Jun 06, 2016 9:30 am    Post subject: Reply with quote

Certainly because some sysadmins don't enable ntp-client and ntpd together ?
Ntpdate sets the correct time immediately (and that may cause some problems, particularly with the logs, and all the services hardly depending on the time, like kerberos-based ones), while ntpd adjusts it smoothly.
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freke
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PostPosted: Mon Jun 06, 2016 6:45 pm    Post subject: Reply with quote

Would a Big ntpd jump be any different from a ntp-client jump?
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Syl20
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PostPosted: Tue Jun 07, 2016 12:55 pm    Post subject: Reply with quote

When, for example, some services complain because their log files have a modification time in the future, yes, that could make a difference. And on a server which provides time to several other computers, disabling ntp-client is a good choice.
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toralf
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PostPosted: Tue Jun 07, 2016 7:00 pm    Post subject: Reply with quote

I do know, how "-g" works.
I do wonder why it is activated for most users as a default value.

Gentoo is about choice

If somebody suffers from time jumps - then that user might add "-g" to his option file. Just because he needs it.
That's why ntp-client (== ntpdate) is not added to default runlevel per default. For the same reason "-g" should not be added as a default value.
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khayyam
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PostPosted: Tue Jun 07, 2016 9:55 pm    Post subject: Reply with quote

toralf wrote:
If somebody suffers from time jumps - then that user might add "-g" to his option file. Just because he needs it. That's why ntp-client (== ntpdate) is not added to default runlevel per default. For the same reason "-g" should not be added as a default value.

toralf ... I disagree, having -g is the more robust, if there is a (big) discrepency in time then without it ntpd will fail, avoding such a failure should be the default option, particularly as it doesn't effect things otherwise (or are you having an *actual* problem due to the fact -g is enabled?).

As I understand it ntpdate should be used in conjunction with ntpd, but as gentoo doesn't add either to a runlevel it's left to the user to decide what is started or not. ITR the presence '-g' is a resonable default ... and users a free to change it.

best ... khay
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