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Re: NTP (not SNTP) on the System i ?



fixed

On 20-May-2014 14:23 -0500, Buck Calabro wrote:
<<SNIP>> NTP will speed up the clock (or slow it down) a bit until
the incoming packets match the system clock. In other words, the
clock will gradually slew onto the new time. With SNTP, the
algorithm is simple, and doesn't slew the clock, it makes up the
difference in one jump, so there's a lurch when SNTP needs to make a
change.

This is why the actual requirement matters. If the requirement is
to avoid large clock changes, you really need to be running an NTP
that can gradually slew the IBM i clock. <<SNIP>>

As I understood the SNTP client for IBM i, there are thresholds that can be set to decide if\how to adjust the time. And if the hardware supports the capability to slow-down or speed-up the system clock, then that throttle feature will be used [within specified thresholds] rather than resetting the time. Notably, for Change SNTP Attributes (CHGNTPA) is this old help-text\documentation for a particular parameter:

_Client adjustment threshold_ (ADJTHLD)
"Specifies the threshold which determines whether changing the clock will require setting or adjusting the clock.

• Setting the clock means replacing the current clock value with a new value. ...

• Adjusting the clock means to incrementally speed up or slow down
the clock so that time is gradually synchronized with the NTP or SNTP time server. Adjusting does not cause the large jumps in time that can be experienced with setting the clock. ...
..."






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