topic Re: system clock about rx4640 in Operating System - HP-UX

system clock about rx4640

lin.chen — Wed, 23 Aug 2006 21:48:21 GMT

this is a very boring problem!
many customer complain that their servers' system clock is slow about 2 or 10 mins every month. how can i solve this problem!

Re: system clock about rx4640

Patrick Wallek — Wed, 23 Aug 2006 21:50:39 GMT

That's easy. Setup the machine as an NTP cliend and point it to one of the myriad of NTP servers available on the Internet.

Search the forums for NTP and you will probably find a lot of information.

Re: system clock about rx4640

A. Clay Stephenson — Wed, 23 Aug 2006 22:43:50 GMT

Computers are terrible clocks. As Patrick said, setup NTP and your problems will be over. Your time will always be accurate to a few tens of milliseconds.

Re: system clock about rx4640

lin.chen — Wed, 23 Aug 2006 22:56:12 GMT

is there any other solution,such as replace the mainboard!if i ask customer to use ntp follow the server on internet.i can not make sure that the ntp server is steady.

Re: system clock about rx4640

Patrick Wallek — Wed, 23 Aug 2006 22:59:30 GMT

No, replaceing the MB will not help the clock. As Clay, these machines are notoriously poor at keeping time.

Now, I should amend what I said above. I said set up NTP and point to 1 of the NTP servers on the Internet. I should have said, point to 3 NTP servers on the Internet. That way you are much more likely to not have any issues with one NTP server giving bad time.

Re: system clock about rx4640

A. Clay Stephenson — Wed, 23 Aug 2006 23:05:49 GMT

The whole point about using NTP servers even over the Internet is that you don't use one server. You use multiple (at least 3) timeservers and NTP itself will determine the quality of the time references and dynamically choose the best of them --- and will switch among them if the current one is poorer than another available server. While trying to use timeservers that are geographically close to you is normally good, it is not necessary. Have a look at the the file /usr/share/doc/NTPprimer.txt. It is an excelllent starting point. Even if you change the motherboard, can you stabilize the temperature and humidity enough so that the time doesn't drift? The answer is NTP; now what is your question?

Re: system clock about rx4640

inventsekar_1 — Thu, 24 Aug 2006 07:44:52 GMT

first GOOD soltion is:
1. buying a Radio clock. It costs. the most accurate time source available.

2. free: NTP sources on the internet. accurate enough.

3. system clock. free.
least accurate.

NTP sources in the internet is the free accurate (than system clock )solution.

Re: system clock about rx4640

Sp4admin — Thu, 24 Aug 2006 08:18:30 GMT

Hi lin.chen,

The OLYMPIAN's have spoken. Look like the NTP solution would be you're best bet.

sp,

Re: system clock about rx4640

Steven E. Protter — Thu, 24 Aug 2006 08:26:02 GMT

Shalom,

Yet another victim of the illusion that a computer clock can tell time.

This goes back decades and is one of the reasons the NTP protocol was invented.

SEP

Re: system clock about rx4640

rick jones — Thu, 24 Aug 2006 19:48:13 GMT

If you should happen to point your system at an NTP server or servers out on the big wide Internet, make sure to contact the admin(s) of those servers. Some "open" time servers would still like you to extend that courtesy.

You don't want to generate a mini D-link fiasco :)

If you have multiple servers, it would be best to have a small number of them (2 or 3) be the ones which contact the Internet servers and then the rest contact those for their time. That way you have redundancy, without putting undue stress on the Internet time servers.

Best of all would be the previous suggestion of getting a radio/GPS time source and having those two or three servers become your own stratum 1 time servers, perhaps even helping-out by serving time on the Internet...