Hirschmann MACH 4000 Series, User Manual

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Synchronizing the System Time of the
Basic - L3P
Release 3.1 06/07
7.4 Interaction PTP and SNTP
119
U
Application example:
The requirements made to network time accuracy are rather high, how-
ever the terminal devices exclusively support SNTP
(see Fig. 33).
In the example above, the left switch receives as the SNTP client the
system time from the NTP server using SNTP. The switch assigns to a
time received from an NTP server the stratum clock number “2”. Thus,
the left switch becomes the reference clock for PTP synchronization.
PTP is active in all three switches, ensuring that, relative to each other,
the system times of the switches are synchronized precisely. As the con-
nectable terminal devices in the example exclusively support SNTP, all
three switches serve as SNTP servers.
Switch 149.218.112.1 149.218.112.2 149.218.112.3
PTP
Operation
On On On
Clock Mode ptp-mode-
boundary-clock ptp-mode-
boundary-clock ptp-mode-
boundary-clock
Preferred Master false false false
SNTP
Function
On On On
Anycast destination address 224.0.1.1 224.0.1.1 224.0.1.1
Server VLAN ID 1 1 1
Anycast send interval 30 30 30
Client External Server Address 149.218.112.0 0.0.0.0 0.0.0.0
Server request interval any any any
Accept SNTP Broadcasts no no no
Tab. 8: Settings for the Example