The 2015 Leap Second: What You Should Know

Keeping time is a tricky business — especially when we’re talking about keeping time at a high precision level.

Every so often our clocks, which tend to follow Coordinated Universal Time, get a little out of sync with the Mean Solar Time.  When this happens, we Earthlings utilize a rather ingenious concept we call a “Leap Second”.  The idea is pretty similar to a “Leap Year”… except that it’s only a 1 second adjustment instead of an entire day.

That 1 second adjustment may not seem like much but, for some functions, high performance timekeeping is absolutely critical (such as for scientific and economic computing needs).

And, as it so happens, on June 30th of this year (2015) — at midnight — one additional Leap Second will be added.

Luckily, if you’re running SUSE Linux Enterprise, you are in good shape. Here’s a quick run-down of the high level information.  (For more detailed notes, see the Knowledge Base article.)

• Running SUSE Linux Enterprise 12?  You’re all set — nothing you need to do here.
• Same goes for SUSE Linux Enterprise 10 or earlier.
• Currently on SUSE Linux Enterprise 11? You’ll want to make sure you’re properly updated to the latest kernel updates in order to make sure you are not impacted. Specifically:
  • SLE 11 SP1 – Kernel 2.6.32.59­0.7 or later.
  • SLE 11 SP2 – Kernel 3.0.38­0.5 or later.
  • SLE 11 SP3 – Not impacted, except for one known issue that will be fixed in the next maintenance update for SP3.