MacBook Pro Network Time Protocol (NTP)

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MacBook Pro Network Time Protocol (NTP)

Hello... I have a brand new 15" MacBook Pro that I'm still getting used to. Although I'm not a new to computers or *nix, I am new to Apple/Mac.

I've noticed that you can update the time with the Mac via the internet using NTP (Network Time Protocol). There were only a few choices from the dropdown so I decided to use a NTP server that I've used quite successfully over the years. I've read some posts on other sites concerning NTP yet none seem to satisfy a few common questions. I'm using a few of those questions here.

1) Can you use your own NTP server address?

2) When does the Mac actually sync with the NTP server listed? Does the Mac sync when it's connected to the internet or does it sync at certain times such as every 20 minutes for example?

3) It doesn't look like there is a setting on the Mac to sync manually to the NTP server such as Windows 7 has (Update now). Is there a way to manually sync to the NTP server on the Mac? If not, is there a command line string that I can use to cause the update to occur manually? What is the command line?

Thank you.

Posted on Aug 11, 2011 10:26 AM

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Answer 1

IrritatedOne Author

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Aug 15, 2011 4:26 PM in response to IrritatedOne

When I type the following in the command line:

sudo ntpdate time-b.nist.gov

(then input the password)

I get the following message:

[date and time] ntpdate[a number]: the NTP socket is in use, exiting

Anyone???

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Answer 2

IrritatedOne Author

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Aug 11, 2011 10:50 AM in response to IrritatedOne

Since this post won't allow me to edit, let me be more specific for question #2.

2) When does the Mac actually sync with the NTP server listed? Does the Mac sync when it's initially connected to the interent (my Mac isn't connected all the time), each time it is connected to the internet or does it sync at certain times when connected to the internet such as every 20 minutes for example?

I hope that's more clear for that question.

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Answer 3

IrritatedOne Author

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Aug 15, 2011 4:18 PM in response to IrritatedOne

Since no-one seems to know the answer, I have a small update. A user can update the host clock of the computer manually by using the following:

From the command line, you can type: ntpdate (network time server address - without quotes)

Example: ntpdate time-b.nist.gov

Here is the problem though. I keep getting the following error message:

[date and time] ntpdate[a number]: bind () fails: Permission denied

I don't know how to get around this. I would like to update the host clock with the time server of my choosing and the above should allow you to do it manually from the command line yet a "Permission denied" is returned.

Telephone tech support didn't know the answer either and advised me to go to: developer.apple.com

Anyone have any answer???

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Answer 4

Nov 4, 2011 8:18 PM in response to IrritatedOne

IrritatedOne:

Hope it's not too late:

Issue

sudo launchctl unload /System/Library/LaunchDaemons/org.ntp.ntpd.plist

this will release the NTP socket ntpd is using.

After you are done with sudo ntpdate time-b.nist.gov

Issue

sudo launchctl load /System/Library/LaunchDaemons/org.ntp.ntpd.plist

I think you don't need these commands, though, because ntpd (ntp daemon) will take care automatically.

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Answer 5

IrritatedOne Author

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Nov 5, 2011 6:26 AM in response to samba2007

samba2007,

I was just looking for a way to sync time manually (not unlike Windows 7) seeing that the user really doesn't know when time is syncd with OS X 10.7 Lion. It looks like this is a lot of trouble with OS X though. I've given up. Thank you for taking the time to reply though. Very appreciated.

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