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Re: Message about ntp when updating



Sthu Deus wrote:
> Not answering to Your question, but as mine opinion - if You do not
> intend other hosts to be sync-ing time w/ this host, I think You need
> the service at all.

Time is important to most internet hosts.  We always hate to see email
from users with a date of 1970 for example.  I would always install
the ntp package to ensure that time is updated on the local host machine.

> For sync-ing time from Internet for the host You can use ntpdate in
> cron/anacron for example.

Please no.  Syncing time from cron is very bad.  It causes the clock
to be stepped and can create very hard to debug behavior.  Setting the
clock from cron is the worst way to do this.

For example if a process is set to trigger at a particular time and
the cron task changes the time out from under it then it will either
trigger early or late or possibly not at all.  For example on a file
server the time is used to set timestamps of files which is used by
the make program and jittery clocks can cause all kinds of strange
make behavior.  And those are just a couple of examples of weird
behavior that is possible.

It is much better to use a smart time protocol aware daemon such as
ntpd which knows how to smoothly adjust the time so that every clock
tick is seen and the time is kept updated without clock steps.

Bob

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