DST problem (template comment does not make sense/incomplete)

[William Hall]

I maybe being stupid but ......

Below from template file yealinkt4x,ph.xml
#Configure the start time of DST. The default value is 1/1/0.
#If the DST type is configured as By Date, the value format is Month/Day/Hour. For example, the value 5/20/10 means the start time is at 10:00 on May 20.
#If the DST type is configured as By Week, the value format is Month/Day of Week/Day of Week Last in Month/Hour of Day.
#For example, the value 1/4/2/5 means the start time is at 5 o'clock on Tuesday of the 4th week in January.

Looking at the by week format ... what does this mean? Easy if one wants Nth Sunday in in a month, one can work it out from the example. I want last Sunday in March (like quite a lot of people), how do I do that? there is mention of "Day of Week Last in Month" but how do I format it? Something like 3/?/7/2

 

[Alphabetic]

You can confirm the date and time layout from the EXT provisioning tab, phones take their time from the PBX so ensure that's set correctly.

 

[JohnS_3CX]

You can control this as @kieferschild said from the extension's provisioning of your specific phone


As for actual time, they sync from ntp.pool.org, but the PBX Timezone defines what timezone they use as an offset when you use global timezone as seen in the screenshot.

You will need to reprovision the phone before the changes take effect.

 

[William Hall]

Thank you all but it's the DST (Daylight Saving Time) settings I'm interested in. I can see how to change time/date format. My global timezone is set to UK(London) but the displayed clock on the phones sdid not advance to summer time at the end of March. Hence me trying to fiddle with the template in the my first post. I suppose I could set the system to Paris time .... but seems a bit silly.

 

[JohnS_3CX]

Please share the following:

- models
- firmware
- PBX version

Exact versions please

 

[William Hall]

3CX Professional Annual V16.0.504 running in cloud
Linux sbc 4.14.69-v7+
Phones: Yealink T19P E2 Firmware: 53.84.0.95

 

[William Hall]

Just did an apt update/upgrade on sbc, it's now:
Linux sbc 4.19.66-v7+ #1253 SMP Thu Aug 15 11:49:46 BST 2019 armv7l

 

[JohnS_3CX]

Ok, so setting your Global Timezone to London in the PBX

and

Setting the phone provisioning options in your extension to "Use Global Timezone" should finally result in the phone being provisioned automatically in the config file it will receive from the PBX as such:


meanwhile

The DST settings are set to start March 28th 02:00 end DST on 03:00 October 25th


The device then calculates based on

a) the timezone offset
b) the DST offset
c) the current clock time it synced off of whichever NTP it finally managed to reach

..and then it decides when to push the clock back or forth. It relies on reaching pool.ntp.org for it's time otherwise it will pick up time from a local NTP you may have (which may present a different time than the online NTP - a point to be aware of).

So long as a) and b) are aligned and c) is correct, then I would expect the phone to change the time the last Sunday in March at 02:00 hours just like you wanted, when provisioned using the default templates, and the PBX timezone is set to London. I can't say if anything was off on the specific day, but if you reset and reprovision the device now using the default template, the phone should end up with the current correct UK time (this will confirm you don't need to make any manual template changes at all).

Hope this helps!