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colin_hill
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NTP issues

Hi (and Happy Christmas/Holidays - depending which side of the pond you are on),

We have a slight problem with out NTP service - We run a number of ESX hosts which are all configured to get their time from the same source.

Every now and then one of them (never the same one) stops updating its time, but when we restart the NTPD service it picks the time up again straight away, which indicates everything is setup correctly.

Any ideas? Is this normal behaviour?

Thanks in advance.

Colin

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nabsltd
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It's not "normal", but it might be working "as intended", as far as the NTP target server is concerned.

If you don't control the NTP server that your ESX servers are getting the time from, you might be accessing it too frequently, or otherwise sending data that causes it to cut off responses.

In general, you should have no more than 5 total machines in your organization use external time sources, and then every other machine will get the time from those 5 machines. Also, if you are connecting to external time sources using 3 or more machines, you really should not use the same external NTP server. Doing so is both bad for the NTP protocol (time is less accurate for your systems) but also not as polite.

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nabsltd
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It's not "normal", but it might be working "as intended", as far as the NTP target server is concerned.

If you don't control the NTP server that your ESX servers are getting the time from, you might be accessing it too frequently, or otherwise sending data that causes it to cut off responses.

In general, you should have no more than 5 total machines in your organization use external time sources, and then every other machine will get the time from those 5 machines. Also, if you are connecting to external time sources using 3 or more machines, you really should not use the same external NTP server. Doing so is both bad for the NTP protocol (time is less accurate for your systems) but also not as polite.

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dkfbp
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Hi,

On the affected server try to look in the log files on the esx console. I have had a similar problem, I don't remember excactly what it was, but the log files helped me.

Best regards

Frank Brix Pedersen

Best regards Frank Brix Pedersen blog: http://www.vfrank.org