Ouster OS1 - Page 90

ExampleNetworkSetup
This section assumes thefollowing network setup asit has elements of alocal master clock and the
optionforan upstreamPTPtime source.
+-------------------------------------+
| Ubuntu 18.04 System |
| * 2x Intel i210 Ethernet Interfaces |
| * Linux PTP service |
| |
| eno1 eno2 |
+-------+---------------------+-------+
| |
+-------+-------+ +--------+------+
| Trimble GM100 | | + +
| GPS -> PTP | | Ouster OS1 | |
| grandmaster | | | |
| (optional) | | | |
+---------------+ +---------------- |
+--------------- +
The focus is on configuring the Linux PTP service to serve a common clock to all the downstream
OusterOS1sensors usingthe Linuxsystemtime fromthe Ubuntuhostmachine.
Optionally,a grandmasterclock canbe addedtodiscipline thesystemtime ofthe Linuxhost.
InstallingNecessary Packages
Severalpackagesareneeded forPTPfunctionality andverification:
linuxptp - LinuxPTP packagewith thefollowingcomponents:
ptp4l daemon tomanage hardwareandparticipateas aPTP node
phc2sys to synchronize the Ethernet controller’s hardware clock to the Linux system clock
orsharedmemoryregion
pmc toquerythe PTPnodes onthe network.
chrony - A NTP and PTP time synchronization daemon. It can be configured to listen to both
NTPtimesourcesvia theInternetand aPTPmasterclock suchas one provided aGPS withPTP
support. This willvalidatethetime configurationmakessense givenmultiple timesources.
ethtool - Atool toquery thehardwareand drivercapabilities ofagiven Ethernet interface.
$ sudo apt update
...
Reading package lists... Done
Building dependency tree
Reading state information... Done
$ sudo apt install linuxptp chrony ethtool
Reading package lists... Done
Building dependency tree
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