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It's Baaack: DST 2007 Causes Y2K Concerns

In August 2005, Congress passed the Energy Policy Act, which changes the dates of both the start and end of Daylight Saving Time (DST). This law goes into effect in 2007, and as a result DST will start three weeks earlier, at 2:00 a.m. on the second Sunday in March, and will end one week later, at 2:00 a.m. on the first Sunday in November.

Some devices that automatically adjust for DST need to be updated for this change. This includes cell phones, PDAs, fax machines, switches, routers, network time protocol appliances, private branch exchanges and industrial and scientific control systems. Without this update, many devices or systems will be wrong twice: once when they fail to change to DST on the correct day, and again when they change to DST on the old date. 

SCCS teams are working to update central and distributed services to correctly deal with this change. The database, file, e-mail and applications servers are being updated to reflect this DST change, so we expect little or no impact for those types of use. Centrally managed desktop systems are also being patched by automatic mechanisms.

Users with non-centrally managed systems, especially laptops, will have to correct their own systems. Desktops or laptops with incorrect times may be unable to authenticate to central servers until they are corrected.

SLAC also has systems that operate more independently and are not fully integrated into the SCCS infrastructure. Some of the operating systems in use around the lab (including Windows 98/ME/2000/NT, VMS, DOS) may require special care and feeding to insure that any interdependencies they may have related to time are addressed. In particular, Java applications may handle time zone management independent of the operating system. And even if there are no direct operational control issues, the accuracy of information (such as tagged scientific data, logs or audit trails) could be compromised or other data become confusing.

Anyone with an independently operating system is encouraged to contact SCCS for support. New information and contact information will be posted online as it becomes available. 

The Y2K problem was largely not a problem on January 1, 2000, because many people took steps in advance of that date to address it. With everyone pitching in, March 11, 2007, should be equally undisruptive.

óGordy Gordon, January 13, 2007