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New Member

NTP Configuration -- Help


I have had some difficulty configuring the NTP protocol based on my timezone.

Here is my problem:

Eastern Daylight Time (EDT) which is 5 hours off from the UTC.

After the time change in October, timezone becomes Eastern Standard time which 4 hours off the UTC.

Now when I configure NTP my time is always one hour ahead like it is EST when we still are in EDT.

Can somebody explain how to make this happens, if possible?

Also, can somebody recommend some NTP servers?

I appreciate your help.

Hall of Fame Super Bronze

Re: NTP Configuration -- Help

For your timezone, you should use:

clock timezone EST -5

clock summer-time EDT recurring

For free public NTP servers, check out:

Please rate this post if it helped, thanks

Re: NTP Configuration -- Help

That is strange, but is the date correct on your router - that is, is it a summertime date.

But there is something funny about your timezones. You seem to have you summer timezone as UTC-5 and your winter as UTC-4. I would have expected it the other way round: EST=UTC-5, EDT=UTC-4. Clocks go forward an hour in summer, not back.

Kevin Dorrell


New Member

Re: NTP Configuration -- Help

You are correct, it is my mistake. Can you provide any information?

New Member

Re: NTP Configuration -- Help

EST (Eastern Standard Time) is UTC -5. That part is configured with:

clock timezone EST -5

To have EDT (Eastern Daylight Time), which is UTC -4, automatically kick in during Daylight Savings, you add the following line to your config:

clock summer-time EDT recurring

Hope that helps!


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