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Use the Airport Express as a local time server System
I just found out that my new Airport Express can work as a time server (NTP server). Looks like a hidden feature, because I didn't find any mention of this functionality in its documentatiion or on Apple's support site. So I set it up to synchronize its clock with time.apple.com. After that was done, I set all my local machines to use this Airport Express as their time server.

Nice little feature and you don't need to drill holes in your firewall for UDP port 123 anymore.

[robg adds: The setting for synching the clock on the AE (and regular Base Stations) is somewhat hiddne. Go into the Airport Admin Utility and click on the Airport tab, then click the Base Station Options button. You can also change how the activity light behaves in this section -- always on, or flashes on activity. I haven't tried using my AE as a time server yet.]
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Use the Airport Express as a local time server
Authored by: theocrates on Aug 11, '04 12:03:30PM

How exactly does one set the base station as the time server in the Date & Time preferences? The pulldown menu doesn't automatically list the base station, and I'm not certain what path to type (e.g., time.apple.com).

Also, Rob, you say one can set the activity light, er, activity; but I don't see anything in my Airport Extreme's "Base Station Options" tab that would indicate as much, unless you mean the Base Station Logging option. (Incidentally, does anyone know what the various logging levels mean? I have mine set to 7-Debug, but I'm not sure what gets logged).



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Use the Airport Express as a local time server
Authored by: GaelicWizard on Aug 11, '04 12:35:18PM

You should type in the IP of the AirPort Express.

Also, AFAIK, if you do not have anywhere for the log to be sent to (which you likely do not) then it does not matter what level you set the log to, because its not being recorded anywhere.

JP

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Pell



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Use the Airport Express as a local time server
Authored by: TvE on Aug 11, '04 01:23:40PM

Not quite true - there is a 128 K buffer in the AirPort Extreme Base Station, so changing to debug level (7) results in more stuff being logged IN the router.

But the best thing to do is to setup a syslogdaemon (Apple has a tecnote on this) if you have a Mac there is acting as a server and is allways on...

PS.: So far I have not see anything being logged "higher" than level 5



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Use the Airport Express as a local time server
Authored by: paulsrandall on Aug 21, '04 03:28:43PM

The activity setting is only available when configuring an AirPort Express Base Station not an Extreme Base Station.



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My firewall does not have a hole for UDP 123 and the timeserver works nevertheless?
Authored by: hamarkus on Aug 11, '04 02:58:15PM

My firewall does not have a hole for UDP 123 and the timeserver works nevertheless???



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My firewall does not have a hole for UDP 123 and the timeserver works nevertheless?
Authored by: cleanhead on Aug 11, '04 04:20:13PM

Mine too under Panther. System time drifted out of synch under Jaguar, however, until I opened port 123. Maybe a bug fixed?



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My firewall does not have a hole for UDP 123 and the timeserver works nevertheless?
Authored by: dsouth on Aug 11, '04 04:30:12PM

The desktop clients initiate the connections to the NTP servers. So unless you've configured your firewall to disallow outgoing connections, the AE will be allowed to connect to ntpd running at time.apple.com, and any macs on your wireless net can connect to the ntpd running on the AE.

Note that, unless you've modified the /etc/ntp.conf file, ntpd will allow other machines to connect and query time. So if you set one Mac/access point/whatever to synchronize with time.apple.com, other machines on the network can synchronize with that machine. Large sites often make use of this to implement several strata of time service.



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Use the Airport Express as a local time server
Authored by: shub on Aug 11, '04 06:47:18PM
You really need to define at least four or five upstream time servers, at a bare minimum. This subject is complex, but please see the discussion at http://twiki.ntp.org/bin/view/Support/SelectingOffsiteNTPServers.

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Use the Airport Express as a local time server
Authored by: applemaster on Aug 11, '04 11:00:31PM

I'm not trying to land a man on the moon, I just want my computer to be able to tell time. If it's off by a few seconds, or even a minute or two, I'm not going to jump off any buildings.

And if the ntp server is completely down, I'll just look at my watch, thank you very much.


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Huh?
Authored by: NeutronMonk on Aug 12, '04 06:34:53AM

On my mac, I have the option under the Date and Time preference panel to have the time automatically set via time.apple.com. No Airport required. No firewall configuring required. Really, really simple.



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Huh?
Authored by: shub on Aug 12, '04 06:51:27AM

The original hint was to use your base station to sync to upstream time servers, and then sync local machines to your base station. This is recommended practice, as it puts lower load on the upstream time servers.

If you define sufficient multiple upstream servers (as I recommended), you can protect yourself against one or more of them going down (the software will automatically find and sync to the best one), and you will also protect yourself against upstream servers that may have bad clocks (again, the software will automatically detect and avoid them).



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Huh?
Authored by: Alrescha on Aug 12, '04 04:55:54PM

You are technically correct - best practices would suggest multiple timeservers, but you are ignoring the fact that this community doesn't have those requirements.

My casual observations lead me to believe that the Airport gets it's time via ntpdate or the equivalent every few hours or so rather than using full ntp, so it's not industrial strength anyway - but more than enough for casual folks who like having a clock with the right hours and minutes on it.

A.



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Use the Airport Express as a local time server
Authored by: shub on Aug 12, '04 06:43:36AM

If you want to use your base station as an NTP server, there's a good chance that it won't be able to get good time sync if you don't follow the recommendations, and if it can't get time sync then it can't provide time sync to any of your internal clients.

If you're going to do this, you might as well make an attempt to do it reasonably well. Otherwise, you cause more problems than you solve.



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Use the Airport Express as a local time server
Authored by: smcneely on Aug 11, '04 09:00:51PM

Actually this seems to work with my Linksys WRT54G  Router
as well...just point my time server field to my local router IP

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~ I try not to say too much...someone might just realize that I don't know what the hell I'm talking about ~



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Use the Airport Express as a local time server
Authored by: rwmitchell on Feb 17, '05 05:15:02PM

Does this still work with the latest firmware? (v5.5.1)

I had all my machines set to sync to my AEBS, and that set to sync to apple. It worked great.

Now I get:

17 Feb 17:10:18 ntpdate[15909]: no server suitable for synchronization found

when syncing to the AEBS



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