Improve accuracy on CMM's NTP service

I have several CMM3 units deployed, and an most people know, it can serve as a NTP timesource. I also maintain a NTP server cluster for my network.

I would love to sync my NTP servers to my own stratum 1 time source (as opposed to relying on the pools), and I have always thought that a cluster manager would be great for that. All of the pieces are currently in place, accept one – the NTP service on the CMM3 (3.0 firmware) rounds its clock to the nearest second!

As an example, go to a Linux box that has IP connectivity to a CMM. Run this command (as root):

ntpdate -d <ip of CMM>

You could clean out some of the extraneous stuff by running:
ntpdate -d <ip of CMM> | grep time


reference time: ce95679a.00000000 Fri, Oct 30 2009 9:24:42.000
originate timestamp: ce95679a.00000000 Fri, Oct 30 2009 9:24:42.000
transmit timestamp: ce95679a.3f3508f6 Fri, Oct 30 2009 9:24:42.246

Notice how the reference time and originate timestamp (what the NTP time server says, and when it said it) is only accurate to 1. second? Yet, the transmit timestamp (when the asking device asked for the time) is accurate to 0.001 seconds. That’s the problem.

If this is intentionally rounded in the software (as I dearly hope), then it should be an easy fix. If the limitation is instead hardware-related, I guess the idea is out the window.

The bottom line is this: a cluster manager is only three significant figures away from being an awesome stratum 1 time source! Is there anything that the Canopy Engineers can do to fulfill that last requirement?

Andy Hull

I agree, that would be awesome, but I’m not so sure it would get a high priority as support for timezones has been on our wishlist for several years… :frowning: