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The Leap Second Is Here! Are Your Systems Ready?

Posted by Soulskill on from the about-time dept.

Tmack writes "The last time we had a leap second, sysadmins were taken a bit by surprise when a random smattering of systems locked up (including Slashdot itself) due to a kernel bug causing a race condition specific to the way leap seconds are handled/notified by ntp. The vulnerable kernel versions (prior to 2.6.29) are still common amongst older versions of popular distributions (Debian Lenny, RHEL/CentOS 5) and embedded/black-box style appliances (Switches, load balancers, spam filters/email gateways, NAS devices, etc). Several vendors have released patches and bulletins about the possibility of a repeat of last time. Are you/your team/company ready? Are you upgraded, or are you going to bypass this by simply turning off NTP for the weekend?" Update: 07/01 03:14 GMT by S : ZeroPaid reports that this issue took down the Pirate Bay for a few hours.

7 of 284 comments (clear)

  1. Re:Irony by at10u8 · · Score: 4, Interesting

    The time service bureaus used to insert leap milliseconds at almost any time. See the bottom plot at http://www.ucolick.org/~sla/leapsecs/amsci.html where there were 29 leaps in 3 years.

  2. as of about a year ago, I started defensive coding by GoodNewsJimDotCom · · Score: 4, Interesting

    Hello, Some of us code our systems somewhat like a finite state machine, and we figure our machine will never operate outside it.

    If you're testing if something that increments ever hits a number(like 10) and goes back to 0, instead of checking if it ==10, check if it is >9.
    There are a lot of defensive coding mechanisms you can use. The downside of this is that when you debug, something can sneak by and put you outside of a state you want, so it makes it ever so slightly harder to debug. But if you're making software that will be used by the public that is hard to give updates, defensive programming can save the day here and there. ,Jim

    --
    God spoke to me
  3. Re:Irony by 0123456 · · Score: 4, Interesting

    I'm interested to hear what the excuse is - because it will probably sound a lot like the things you all flame Windows users for...

    A lot of Linux systems are on private networks and have to be up 24/7. Dealing with a known bug is considered less problematic than installing a new OS version and invalidating all the testing which has proven that the system can run 24/7 over the last few years.

    So I guess you're right, it is very similar to the reasons why there are many unpatched Windows systems out there.

  4. Leap second got Reddit? by daff2k · · Score: 4, Interesting

    Looks like Reddit's systems weren't ready for the leap second. It been down since around midnight (UTC). You'd think a site as big as that would be ready for such an event.

    --
    And which parallel universe did you crawl out of?
  5. Terminology? by Anonymous Coward · · Score: 2, Interesting

    If 2012 is a leap year, doesn't that make 2012-06-30 23:59 a leap minute?

  6. Re:Android by at10u8 · · Score: 3, Interesting

    anything that runs its kernel on GPS time can give correct UTC time by following this prescription http://www.ucolick.org/~sla/leapsecs/right+gps.html

  7. Re:Irony by Hognoxious · · Score: 3, Interesting

    Microsoft doesn't force anyone to update. You are in control of your updates in Windows, just like in Linux.

    Nope. I have windows update set to "check but ask" and occasionally I find that it's restarted due to updates without even informing me.

    --
    Confucius say, "Find worm in apple - bad. Find half a worm - worse."