|
|
Posted by Unruh on 06/30/07 19:15
ibuprofin@painkiller.example.tld (Moe Trin) writes:
>On Wed, 27 Jun 2007, in the Usenet newsgroup comp.os.linux, in article
><1383dmujf7mp67a@corp.supernews.com>, Gordon Burditt wrote:
....
>I'd change network providers too. In the thirty-four years I've been
>in networking, the longest we've been disconnected is six hours - the
>classic 'backhoe fade' thanks to the city water department. But if
>you are dependent on network connectivity, haven't you at least looked
>into disaster scenarios? Or do disasters only happen to others? I know
>that your bank is going to be in really deep sh!t if they're off line
>that long - both from the government regulators AND their ex-customers.
Look, if you are really that desperate for accurate times, get a gps
receiver with pps capability. That will keep your system accurate to
microseconds . And it will not go off when your network disconnects.
And they are cheap ( the one I bought was less than $100)
Use ntp to sync to it, not to th enetwork ( which is certainly not good to
even msec, never mind microseconds).
Then slave your other computers to that one as a stratum 1 server.
>>NTP does correct for some of the error. Then again, the clock error
>>depends on temperature by quite a lot.
>Please remember than companies that are subject to these legal
>requirements (about not fscking with the clock) are also not dependent
>on a single PC in an uncontrolled location. Thus, there are three time
>servers here, each monitoring _separate_ time sources, and averaging
>that to 'tweak' their own concept of correct time, and we're not even
>subject to those regulations - they are only serving time to 2500+ users
>in this facility, and acting as a stratum 4 reference to other time
>servers in other company locations.
Why not get a gps clock with the network as backup?
Navigation:
[Reply to this message]
|