A leap second will be added on June 30, 2015 23:59:60 UTC. If you are not familiar with leap seconds, read below to see what it is, how it may impact you and how to prepare for it. If you have experience with managing leap seconds, feel free to read through the post as a refresher or skip to the summary and check out the applicable links provided below.
What is a Leap Second?
A leap second is occasionally added to account for the Earth’s rotational displacement. When this phenomenon occurs, 1 second is added to the atomic clocks to synchronize time. These adjustments are made because atomic clocks (primary source for universal time keeping) are designed to tick and keep time very accurately, more so than Mother Nature. Studies have shown that the atomic clocks will only deviate 1 second in 20 million year whereas leap seconds occur more frequently. To be exact, there have been 25 leap seconds recorded for since 1972.
How does this impact my business?
For the general public, this will go unnoticed. However, it is critical for IT Professionals to oversee the leap second implementation where timed transactions and precise time stamping are essential. One line of business that falls into this category is the stock exchange and markets where 1 second can mean millions of dollars. Legacy and infrequently patched systems may also be susceptible if they have not been patched. According to Network World, in 2012 (the last leap second), there were several cases where unpatched systems crashed. Foursquare, LinkedIn, Yelp, and Mozilla were among those that were impacted.
How do I prepare of Leap Second?
System administrators should verify that their system clock sources are consistent and synchronized. This will generally come into play if you are running clustered services. Application engineers should also review applications that are known to be sensitive to time mismatches and prepare to take action in case their applications fail. You can also check with your vendors to make sure that their products are supported for leap and review support documentation on known issues. Finally, inform your clients about the potential risk in advance.
Overall, I wouldn’t consider leap second to be an Y2K-like epidemic. However, this is a case where it is better to be safe than sorry because leap seconds can potentially wreak havoc. Moreover, if you do run into a system/application crash on June 30th, 2015 23:59:60 and you can’t explain why, be sure to check your system clocks.