How do I interpret w32tm output, especially d:?

I am trying to understand what all the different values mean in the following output. I understand the command below is comparing my local time ("current time is") with time.nist.gov

8:38:08 is my local workstation time.

What does the value in d: mean? What does the value in o: mean?

C:\>w32tm /stripchart /computer:time.nist.gov
Tracking time.nist.gov [131.107.13.100:123].
The current time is 3/5/2015 8:38:08 AM.
08:38:08 d:+00.0311860s o:+00.2011040s [ |* ]
08:38:10 d:+00.0311843s o:+00.1896103s [ |* ]
08:38:12 d:+00.0311849s o:+00.1905021s [ |* ]

I think I understand o: to mean that if I take my current time and add the o: value, then my local time will be in sync with remote time. I tried by adjusting my time ahead a few seconds. Since the o: value changed to -00.3849046s, I assume that means my local time is ahead and I need to slow it down to be in sync:

C:\>w32tm /stripchart /computer:time.nist.gov
Tracking time.nist.gov [24.56.178.140:123].
The current time is 3/5/2015 8:43:06 AM.
08:43:06 d:+00.0467946s o:-00.3849046s [ *| ]
08:43:08 d:+00.0311896s o:-00.3815899s [ *| ]
08:43:10 d:+00.0439942s o:-00.3595516s [ *| ]

This also leads me to believe the | symbol is local time and the * is the remote time. * to the left means your time is ahead. * to the right of it means your time is behind.

That still leaves d:... is that ping latency? Do I need to add those seconds with o: to get the final time of the remote time server?

1 Answer

How do I interpret w32tm output?

08:38:08 d:+00.0311860s o:+00.2011040s

• 08:38:08 is local time

• d:+00.0311860s is the internal delay (time difference between the udp package received and udp package sent on the server side

• o:+00.2011040s is actual offset between the local time and the server time

That still leaves d:... is that ping latency?

Do I need to add those seconds with o: to get the final time of the remote time server?

The o: is the actual offset, so you don't need to add the d: to get the final time.

The console application w32tm.exe allows monitoring of the offset of the local time to the time of an internet time server.

The easiest way to do this is from a console window with the following set of parameters:

w32tm /stripchart /computer:time.windows.com /period:120

As a result, the system time and its offset to the time server are dumped to the console every 120 seconds:

Tracking time.windows.com [65.55.21.14.123]

08:38:57 d:+00.0417301s o:+00.1024506s [ * ]

Each line consists of the local time (08:38:57), an internal delay (time difference between the udp package received and udp package sent on the server side, i.e., d:+00.0419394s), the actual offset between the local time and the server time (o:+00.1024506s) and a very basic stripchart of the offset.

Source Part II: Adjustment of System Time