3Com 4200G 12-Port Configuration Manual page 319

NTP Multicast Mode
Configuration
1 Configure S4200G 3.
Root delay: 27.47 ms
Root dispersion: 208.39 ms
Peer dispersion: 9.63 ms
Reference time: 17:03:32.022 UTC Thu Sep 6 2001 (BF422AE4.05AEA86C)
The output information indicates that S4200G 1 is synchronized to S4200G 3, with
the clock stratum of 3, one stratum higher than S4200G 3.
d Display the information about the NTP sessions of S4200G and you can see that a
connection is established between S4200G and S4200G3.
[S4200G] display ntp-service sessions
source
********************************************************************
[1]3.0.1.31 0.0.0.0
note: 1 source(master),2 source(peer),3 selected,4 candidate,5
configured
Network requirements
S4200G3 sets the local clock to be NTP master clock, with the clock stratum of 2. It
advertises multicast packets through VLAN interface 2.
Configure S4200G 1 to listen multicast packets through their VLAN interface 2.
This example assumes that S4200G 3 is a switch that supports the local clock being
the master clock.
Network diagram
Figure 97 Network diagram for NTP multicast mode configuration
Configuration procedures
a Enter system view.
<S4200G> system-view
System View: return to User View with Ctrl+Z.
[S4200G]
b Enter VLAN interface 2 view.
[S4200G] interface vlan-interface 2
c Configure S4200G 3 to be a multicast server.
[S4200G-Vlan-Interface2] ntp-service multicast-server
refid st now
2 1
Configuration Example 305
poll reach delay offset
64 377 26.1 199.53
dis
9.7