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does daylight savings shift affect switches?

Walter Kiczko
Occasional Advisor

does daylight savings shift affect switches?


With all the recent noise about the daylight savings shift, will my HP 4000's and HP 2524's log & event files be time stamped incorrectly?

Will firmware patches be released?

I am pointing my switches to a network time server, so I wonder if the daylight setting in the switch is ignored if I am not setting manual time on the switch.

thanks for any feedback or solutions.

Ron Kinner
Honored Contributor

Re: does daylight savings shift affect switches?


Says they will make patches available but I don't see any yet.


NTP only cares about UTC (GMT) as far as I know. The change in hours from GMT is handled by the receiving box if you tell it what time zone it is in and if it has to worry about Daylight Saving Time. If you don't then it stays at GMT. You can probably log on to a switch and do

show clock

and it will probably tell you what time it thinks it is.

Can't say for sure what time stamp is used by the syslog function but the last time I looked there was no way to report your time zone in the syslog message so I expect that you will see whatever time the reporting box thinks it is. So if your switch is thinking it's in the EST timezone then it will report errors in EST until the old EDT change date comes around.

That's one reason we always used GMT throughout our systems.

Mohieddin Kharnoub
Honored Contributor

Re: does daylight savings shift affect switches?


The Syslog, Debug or any Event generated by the Switch will be stamped by the current time of the switch.
Also the ProCurve 4000M and 2500 series provide a way to automatically adjust the system clock for Daylight Savings Time (DST) changes.

Also, you can you define the month and date to begin and to end the change from standard time.

Anyway, there are five pre-defined settings for DST and one User defined allows you to customize the DST configuration by entering the beginning month and date plus the ending month and date for the time change.

Check the following, page 404:

Good Luck !!!
Science for Everyone

Re: does daylight savings shift affect switches?

i don't know if HP is updating firmware for the DST issue, but they have config samples for using the user-defined option to set your own DST rule.