Re: Time Puzzle (and DST update about the web link)

Karl,
Are you running Network Time Protocol (NTP)? Did you have a
misconfigured NTP server in your NTP configuration?

Without Network Time Protocol (or another clock discipline method), most
clocks will use the AC cycle (60 HZ in the USA) as their reference
frequency and will drift wildly depending on the quality of the power.
Power conditioning will help, but NTP should keep the clocks in sync
with each other. There are NTP hardware devices (appliances) that
receive radio signals that are broadcast by governments that keep your
clocks in sync with a national standard clock.

Also, if you lose power and switch to a local generator, the quality of
the power from a local generator tends to vary frequency by the load of
the generator, this will drive the clocks crazy too. I found this out
when I ran my alarm clock off a generator that was running at 62 HZ. By
morning, my alarm clock was significantly ahead of my battery-powered
clocks!


Edward Davignon
Lead Analyst - Distributed Systems
Utility Shared Services - IT
Energy East Corporation

-----Original Message-----
From: IBM AIX Discussion List [mailto:aix-l@xxxxxxxxxxxxx] On Behalf Of
Karl Jones
Sent: Friday, February 02, 2007 10:03 AM
To: aix-l@xxxxxxxxxxxxx
Subject: Re: Time Puzzle (and DST update about the web link)

I have not been experimenting with TZ. Further, in one instance, the
user is me from a machine which I know is set for the same time zone.
Nevertheless it is the only lead I have so far so I will look into it.

Andrew.Townsend@xxxxxxxxx wrote:
Let me guess, you're experimenting with the TZ ?

I am testing the chtz command and I have seen that same thing as well.

By the way, if you are looking at this website that shows you how to
change
the timzone information to reflect the upcoming changes in Daylight
Savings
Time (only for those of use that aren't at the supported level):

http://www-1.ibm.com/support/docview.wss?rs=0&uid=isg3T1000252

The command on the website shows this command (For EST):

chtz TZ=EST5EDT,M3.2.0/2:00:00,M11.1.0/2:00:00

The command should be:

chtz EST5EDT,M3.2.0/2:00:00,M11.1.0/2:00:00

I called IBM and told them so hopefully it will be changed on the
website
soon.

Once the command is run, check the /etc/environment and look at the
TZ=
line. If you use the command shown on the website you will see:

TZ=TZ=EST5EDT,M3.2.0/2:00:00,M11.1.0/2:00:00

what you want to see is:

TZ=EST5EDT,M3.2.0/2:00:00,M11.1.0/2:00:00

Drew





Karl Jones

<kjones@stpaullin

ocpt.com>
To
Sent by: IBM AIX aix-l@xxxxxxxxxxxxx

Discussion List
cc
<aix-l@Princeton.

EDU>
Subject
Time Puzzle



02/01/2007 04:47

PM





Please respond to

kjones@stpaullino

cpt.com









I am puzzled by the date stamps here. How is this possible?

Last unsuccessful login: Thu Feb 1 20:58:34 2007 on ssh from
221.208.160.11
Last login: Thu Feb 1 21:32:06 2007 on ssh from karl-jones
[snip]
F50:/ # date
Thu Feb 1 15:32:40 CST 2007



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