* Congress gives us another IT problem with new Daylight Saving Time
This year Congress has, in its wisdom, given us another IT problem to deal with: They have moved the start of Daylight-Saving Time by three weeks to the second Sunday in March (March 11) and end it one week later on the first Sunday in November (Nov. 4).
This new schedule is the result of the Energy Policy Act of 2005 and the idea is that (as you may have guessed) we will save energy. Of course, dealing with all the computer systems that need to be modified will cost us millions of dollars in manpower and resources and the Department of Energy doesn’t yet know if we will actually save significant amounts of energy and its study won’t be published until late 2007 but we’re doing it anyway … sigh.
A good discussion on the DST program and how it is implemented in the U.S. and the EU can be found on the online museum WebExhibits. A definitive source of information on the change can be found on the U.S. Naval Observatory’s Web site.
I think we all know from the totally unwarranted Y2K foolishness that this change will not be a dramatic end-of-Western-civilization-as-we-know-it event. That said, neither is it something we can ignore because its potential impact on Web applications could be significant.
A major problem with the new DST start is that the adjustment is made on each individual computer – the time servers you rely on for synchronizing time across your enterprise provide UTC time (i.e. Greenwich +0 hours) time.
Where this becomes a real issue is with operating systems created before 2005 which will probably be set up to make the changeover on the old date – see the Network World article “Daylight saving time: What’s up with those time servers?” and “Daylight-saving changes: No Y2K, but there could be headaches”.
So what’s Microsoft doing about this? They have a page that points to various articles on the topic. Here’s the bottom line: If you have Windows XP SP2 or later there’s an “Optional” windows update which you must explicitly select to have installed until mid-February when Microsoft will move the update to “Critical.” After that time if you have Windows Update enabled the update will be automatically installed. Windows XP SP1 and earlier version will need to be upgraded to SP2 or later for the update to be available.
For earlier Windows systems you can use Microsoft’s TZedit tool, which is explained in detail on the company’s page “How to configure daylight saving time for the United States in 2007”.
There’s also a tool called timezone.exe, but if you are using Java you need to read IBM’s very useful note on the new changes to DST as this utility can apparently cause problems with what date and time Java will use.
For Java users Sun has also released Java 1.4 and 1.5 updates to address the problem, and note that Java SE 5.0 u6 and later have the correct time zone information.
Some other DST notes from a friend:
1. tzdata and glibc-common patches have been released for Linux.
2. mysql_tzinfo_to_sql can be used to load the updated time zone tables into MySQL after applying O/S patches.
3. MySQL time zone description tables for Windows and HP-UX are available.
4. Solaris updates are available.
So if you haven’t conducted an audit of your time keeping strategy (you do have one don’t you?) and figured out what you need to do, then now is the time to begin because when the new DST starts you better get it right. While Western civilization might be quite safe, not being ready could easily mean that your systems (and your job) could well experience a bump in the road.
