Blog

6Feb
2007
ColdFusion And Daylight Savings Time Changes

With the changes to Daylight Savings Time in the U.S., some of you have been asking about how this impacts ColdFusion. The following technotes explain all:

Comments (15)



  • Sensei Loco

    Thanks Ben! Very useful information as we start to research potential problems around here.
    BTW, why doesn't the captcha work for me in Firefox? All I get is a black box w.'Captcha Not Available' written inside. :(

    #1Posted by Sensei Loco | Feb 6, 2007, 05:44 PM
  • Ben Forta

    Odd, I am using FF and see the captcha image right now. What version of FF?

    --- Ben

    #2Posted by Ben Forta | Feb 6, 2007, 06:04 PM
  • Sensei Loco

    Hm...I'm on my linux box and it looks fine. Must be something strange w.my 'Portable Firefox' I run @ work...or their horrible horrible proxy. :) [http://portableapps.com/apps/internet/firefox_port...]
    I'll use IE if I ever comment again @ work. Sorry for the trouble & feel free to delete this comment. :)

    #3Posted by Sensei Loco | Feb 6, 2007, 08:20 PM
  • Gary Funk

    I just want to note that it is Daylight Saving Time. Not Savings.

    #4Posted by Gary Funk | Feb 6, 2007, 10:13 PM
  • Greg Nilsen

    I keep getting "Connection Reset" messages in FireFox when I try the CF5 link.

  • Joe Mastroianni

    One comment on the JVM update:

    In the jvm.config take note that the slashes in the path to the new JRE are FORWARD slashes and not BACK slashes. I was pasting the path in from Windows Explorer without really paying attention.

    #6Posted by Joe Mastroianni | Feb 7, 2007, 10:07 AM
  • David O Malley

    Ben,
    I was under the impression that CF (7 in my case) took the sytem date from the host computer - is that not the case? If it IS the case, do we still need to install the new JVM? If I am wrong in my assumption, is it possible to set the date/time for one CF instance to be differen to the others? (I only ask because this would be good for testing).

    For the record, we are set up with the multi-server install.

    Cheers,

    David

    #7Posted by David O Malley | Feb 8, 2007, 03:03 PM
  • Lost

    Hmmm.

    I downloaded the new "j2sdk1.4.2_11" and unpacked it to the "C:\Program Files\Java" on the server. Modified the "jvm.config" file to read:

    java.home=C:/Program Files/Java/j2sdk1.4.2_11

    After I restart the services I see in the CF admin that it is still using the
    Java Home: C:\Program Files\Java\j2re1.4.2_08

    Did I miss a step? Does the whole server need to rebooted?

    Thanks for any help.

    #8Posted by Lost | Feb 15, 2007, 07:45 AM
  • Lost

    Disregard. I'm a slow this morning. Multiserver configuration. Looking in the incorrect "jvm.config" file.

    Thanks anyway!

    #9Posted by Lost | Feb 15, 2007, 07:52 AM
  • Cris Mooney

    Win OS DST 2007 patch may require full OS reboot in some cases.

    We run CF "7,0,2,142559" on Sun's JVM "1.5.0-b64", and on our Feb 28 JVM restart (just service, not OS) some of our production servers reported that ColdFusion was off by 5 hours. Presumably the source was the Sun JVM, and being we are EST we believe it reverted to GMT.

    The hosting group reported that they had applied the Windows DST 2007 patches (http://support.microsoft.com/kb/931836/) to all these machines, sometime between last JVM restart and the current restart.

    In our case a full OS reboot of the problematic web servers solved our time issue. The only difference we could find was that the problem servers had been up 48 days, while the others had been OS rebooted recently. Presumably, the Win OS DST patches were applied without OS reboot, and the JVM restart did not sync well without full Win OS reboot.

    On a side note, "1.5.0-b64" is not patched for DST March 11 as noted at "http://java.sun.com/developer/technicalArticles/In...;, since "1.5.0xxx" is the same as "5.0xxx", and we need "u6" (update 6) not an earlier beta.

  • betagreg

    something I can't tell from the CF5 workaround: should we always be subtracting an hour before using dateconvert() or is it only during the extra week before and after the previous DST timeframe?

    #11Posted by betagreg | Mar 7, 2007, 02:18 PM
  • betagreg

    nevermind, found a better explaination of the TechNote at Sarge's Blog:

    "UTC conversions will be off by an hour during the new DST periods --i.e. from March 11 (new DST start) - April 1 (old DST start)"

    #12Posted by betagreg | Mar 7, 2007, 03:53 PM
  • Alexander

    The technote URL does not work anymore for Coldfusion 7 (Jrun).

    Any idea please?

    Thanks,
    Alex

    #13Posted by Alexander | Mar 27, 2007, 10:51 AM
  • John

    Very helpfull, Ben
    you can also see
    http://kb.adobe.com/selfservice/viewContent.do?ext...

    #14Posted by John | Sep 13, 2007, 11:16 AM
  • Jose

    I'm running 1.4.2_11-b06 but the time is still one hour ahead. I also ran the tzupdater tool, just in case. Also, CFMX has been restarted. What could be the problem?

    #15Posted by Jose | Nov 1, 2007, 10:59 AM