Polycom VVX Phones and UK Daylight Savings Time

This weekend just past, the UK observed the end of daylight savings time for another year, bitterly welcoming in the cold weather and the start of the dark months. With that comes the day that many administrators dread in fear that their devices and equipment will fail to update with the proper time. Suffice to say, I have learnt lessons from previous years and my servers and network equipment all survived to tell the tale, however, I noted this morning that my Polycom VVX 500 desk phone had not.

I was surprised by this as I had all the proper configurations in place to ensure that the phone was using the correct time zone, however, upon investigation, the phone does not link the DST setting to the time zone: DST is configured separately. After a couple of minutes tweaking it via the web interface, I extracted the configuration, made it pretty and here it is.

Please feel free to use this on your own Polycom Provisioning Server configuration file if you have found your own phones now behaving. The configuration does a few things and hopefully, it should be clear enough for you to modify for your own needs in other locales.

  • Forcibly enable DST
  • Forcibly set DST to occur on a fixed schedule
  • Set DST to start on the last Sunday of the third month (March)
  • Set DST to end on the last Sunday of the tenth month (October)
  • Set DST to begin at 1 a.m. and end at 2 a.m.


<tcpIpApp.sntp.daylightSavings tcpIpApp.sntp.daylightSavings.enable="1" tcpIpApp.sntp.daylightSavings.fixedDayEnable="1" />
<tcpIpApp.sntp.daylightSavings tcpIpApp.sntp.daylightSavings.start.month="3" tcpIpApp.sntp.daylightSavings.start.dayOfWeek.lastInMonth="1" tcpIpApp.sntp.daylightSavings.start.time="1" />
<tcpIpApp.sntp.daylightSavings tcpIpApp.sntp.daylightSavings.stop.month="10" tcpIpApp.sntp.daylightSavings.stop.dayOfWeek.lastInMonth="1" tcpIpApp.sntp.daylightSavings.stop.time="2" />