DST change and home auto...

| I manage several networks running mostly XP pro all syncing to local | Linux servers running NTP. The problem is that M$ in their wisdom | allowed machines syncing to a LOCAL time server to calculate DST offsets | at the machine level. This is madness.

What else could they do? Are you suggesting that there is some way to get timezone information from an NTP server (local or otherwise)?

| I used WindowsXP-KB931836-x86-ENU.exe on any machines that had SP2 and | tzedit.exe on the others to get the clocks right. Unfortunately these | patches only correct the time not fix the root of the problem since the | time offset is still calculated on the local machine.

I don't know about the patch, but tzedit fixes the root of the problem as far as the machine is concerned. The interesting issue is binaries that incorporate their own DST rules, most commonly in tzset in the C library. At least as far back as 1996 (that's just the source that I have handy) the MSC Windows library tzset calls GetTimeZoneInformation(), so anything using that should be ok. Old DOS binaries are of course a problem since all (as far as I know) MSC DOS libraries had hard coded rules in tzset. I was lucky enough that someone sent me the sources for the MSC 6.00 DOS libraries so I could fix tzset and recompile all my programs that depend on it. It might be interesting to know whether the hard coded rules ever made it into any older version of the MSC Windows libraries; that would be something to watch out for.

Dan Lanciani ddl@danlan.*com

Reply to
Dan Lanciani
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Not exactly.

My feeling is that if you specify a machine as the timeserver on the subnet (especially a private IP range) then the client machines should use the time they receive without adjustment. In most cases this is what the network admin needs. Letting the local machines "fiddle" with timezones and DST adjustments causes more problems than it solves.

Reply to
Lewis Gardner

In article , snipped-for-privacy@simplifiedtechnologies.com (Lewis Gardner) writes: | Dan Lanciani wrote: | > In article , snipped-for-privacy@simplifiedtechnologies.com (Lewis Gardner) writes: | > | > | I manage several networks running mostly XP pro all syncing to local | > | Linux servers running NTP. The problem is that M$ in their wisdom | > | allowed machines syncing to a LOCAL time server to calculate DST offsets | > | at the machine level. This is madness. | > | > What else could they do? Are you suggesting that there is some way to | > get timezone information from an NTP server (local or otherwise)? | | Not exactly. | | My feeling is that if you specify a machine as the timeserver on the | subnet (especially a private IP range) then the client machines should | use the time they receive without adjustment. In most cases this is what | the network admin needs. Letting the local machines "fiddle" with | timezones and DST adjustments causes more problems than it solves.

The time you get from an NTP server (local or otherwise) is UTC. If you use that time without adjustment you will be running GMT.

Dan Lanciani ddl@danlan.*com

Reply to
Dan Lanciani

NTP, IIRC, uses GMT, and DST/TZ is specific to the "endpoint". That's why I can hit a time server two zones away and have my machines display the correct local time.. If you look at the NTP specs, I'd bet you see that time is always GMT/UT. Imagine if someone did a NTP server that adjusted for "local" time and the client assumed GMT/UT. Your coffee would start when you just went to bed with a HA system!

I do have a local NTP server on my net that syncs with a real time server. Other local boxes sync with the local server, but only to reduce unneeded external traffic.

I'm in MT, and it's MST 12 months a year (we don't do DST in AZ)..

Reply to
AZ Woody

EXACTLY! NTP isn't just "something somebody came up with and put in the public domain" but is a defined spec - like FTP, SMTP, SNMP, IP, TCP, etc!

Reply to
AZ Woody

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