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Daylight Saving Time

Being a hospitality telecommunications technician, I am very sensitive to DST events because they have the potential to disrupt wakeup calls.  As such, I've learned a few tricks for dealing with DST in windows (because many voicemail systems are windows-based).  But I'm going to start with a boring background and cover some PBXs before getting into the VM (and windows) systems.


In accordance with the Congressional Energy Policy Act of 2005, as of 2007 Daylight Time begins on the second Sunday in March (at 02:00 AM), and ends on the first Sunday in November (at 02:00 AM). Apparently they haven't completed their study, or simply decided not to put everyone through the hassle of changing DST rules again, because this act still applies. I, for one, wish we were just on Daylight Time year-round! SEC. 110. DAYLIGHT SAVINGS. (a) Amendment.--Section 3(a) of the Uniform Time Act of 1966 (15 U.S.C. 260a(a)) is amended-- (1) by striking ``first Sunday of April'' and inserting ``second Sunday of March''; and (2) by striking ``last Sunday of October'' and inserting ``first Sunday of November''. (b) Effective Date.--Subsection (a) <<NOTE: 15 USC 260a note.>> shall take effect 1 year after the date of enactment of this Act or March 1, 2007, whichever is later. (c) Report to Congress.--Not <<NOTE: 15 USC 260a note.>> later than 9 months after the effective date stated in subsection (b), the Secretary shall report to Congress on the impact of this section on energy consumption in the United States. (d) Right to Revert.--Congress retains the right to revert the Daylight Saving Time back to the 2005 time schedules once the Department study is complete.

Mitel PBX
   Mitel 200 PBXs support DST back until some revision of about LW17 (K33 is the oldest I've seen with DST).  I haven't pinpointed it exactly, but if the 200 has system options 73 and 76, you're good for DST programming.  There's also option 79 (DST offset in minutes), but I don't know when it wouldn't be 60.  In the Mitel, options 73 and 76 operate independently of each other.  Option 73 specifies a time to 'spring forward' or 'advance to daylight time' while option 76 specifies a time to 'fall back' or 'return to standard time.'  Each option specifies the DST event time in month:day:hour format (MM:DD:HH).  Once these times hit (and the option is used) the PBX will adjust the values by converting the month value to 00.  This is an indication that the option is disabled (and prevents the PBX from infinitely falling-back).
    Fancy new Mitels (the 3300) can be upgraded to MCD.  MCD *finally* lets you configure NTP settings.  It only took mitel about 5 years after "IP-enabled" became standard to figure out NTP, but at least they're getting there!

Avaya PBX

    Avaya PBXs have had DST since release 7.  In the Avaya, you program a DST rule using the 'change day' command.  The rule specifies both a start and an end time.  You can see the active DST rule with the 'set tim' command.

    Intuity VM systems require a reboot for some stupid reason when the time is changed.

Innline 2020

    Innovations VM application has been known to not recognize changes to DST rules.  If DST rules are changed, the VM application *must* be restarted.  But innovations seems to have gotten DST registry correct, and I've added an attachment to this page.  This one windows registry hack will correct DST in all windows systems (including NT)!  Not even Microsoft made it this easy; their registry hack does not apply to NT, and their time application doesn't always read correct data from the system.  Here's a relevant article if you want to start getting frustrated.
    But there is a trick to applying this patch!  You must first disable windows from adjusting time in accordance with daylight savings, then apply the registry patch, then re-enable DST.  After all this, you must restart the innline application.
    Sometimes I have more free time than I should, or I just make things harder than they need to be.  In this spirit, I made an "ITW Decision Tree" which outlines the process for changing the time on a windows-based Innovations VM.  Find it attached to this page.

Windows PCs

    NIST is a great organization.  Atomic time is lots of fun.  The History Channel had a special on measuring things, and time was included; it was awesome.  They are super-big dorks at NIST, as evidenced by their use of MS paint to draw on their PDF describing part of what I'll be parroting later.  I find page 6 hilarious.

    Moving on!  As I mentioned in the Innline 2020 section, I once found a timezone/dst utility produced by MS.  This utility is not worth mentioning it's so unreliable, and though I am mentioning it, I won't bother to find the link again.  NIST produces a timezone utility that isn't very attractive, but is very effective.  Here's the link (I've also attached it to this page)!  To see your DST settings, run the application, click "Daylight Time" then "System Setting."  A dialog box will pop up that'll tell you the start and end dates, and whether or not you're currently on Daylight Time.
Now that's effective!  And what's more is that I've found it to be accurate across all systems I've run it on.  This includes all variants of windows back to NT4.

The only trick to using this utility is that it won't give you accurate information if your system isn't configured to automatically adjust to daylight saving time.  You can configure this setting by double-clicking your clock and selecting the 'time zone' tab.  Find the check-box at the bottom.   See the Innline 2020 section for how to patch windows registry to correct these values if they're wrong.

Windows PCs + Internet Time

By default, windows has an "Internet Time" option, but it only lists "time.windows.com" and "time.nist.gov," and neither ever seem to work by default.  I'm sure this is no fault of NIST, but rather the Microsoft's implementation of NTP that is to blame.  Anyhow, I turned to NIST for a solution, and I wasn't surprised to find they had one.  I attached their hilarious PDF to this page.  It basically says to run the following lines.  Please notice that I populated the code below with my own choice of time servers.  I suggest you choose your own servers from this site.
net time /setsntp:"nist1.columbiacountyga.gov time-a.nist.gov time-nw.nist.gov"
net stop w32time
net start w32time
Now I'll have to admit that I asked google how to fix this before I asked NIST.  And google let me down.  I found sites that gave me suggestions, but what I ended up with was an error 1058 when attempting to start the time service.  Luckily, though google told me how to fix this!  If you (like me) diddled with your windows time service and broke it, you can simply unregister the service, reboot, and re-register the service.
w32tm /unregister
w32tm /register
Matthew R Chase,
Mar 9, 2010, 2:05 PM
Matthew R Chase,
Mar 9, 2010, 2:31 PM
Matthew R Chase,
Mar 9, 2010, 2:08 PM
Matthew R Chase,
Mar 9, 2010, 2:07 PM