And the Time Is …

Charly's Column – ntpviz

Article from Issue 228/2019
Author(s):

The Network Time Protocol allows admins to keep time on their computers. Due to the way the system works, this timekeeping is only moderately successful. Charly uses the ntpviz statistics tool to visualize time fluctuation.

I recently browsed the NTPsec repository [1], a heavily reworked fork of the well-known Network Time Protocol daemon, ntpd. The newcomer is looking to ditch legacy ballast and finally provide protection against Man-in-the-Middle attacks. NTPsec is not the topic today, but I would like to talk about a small tool that I found while browsing: ntpviz. Among other things, the program visualizes the extent to which the time queried by the NTP server deviates from the local time (offset) and how strongly it fluctuates (jitter).

To get started, I cloned the Github repository and started the installation:

cd /usr/local
git clone --depth 1 https://gitlab.com/NTPsec/ntpsec.git
cd ntpsec
./buildprep
./waf configure --refclock=all && ./waf build && ./waf install

[...]

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