3Com MSR 50 Series Configuration Manual page 2069

Because Router A and Router C are on different subnets, you must enable IGMP
on Router B before Router A can receive multicast messages from Router C.
# Enable IP multicast routing and IGMP.
<RouterB> system-view
[RouterB] multicast routing-enable
[RouterB] interface ethernet 1/0
[RouterB-Ethernet1/0] pim dm
[RouterB-Ethernet1/0] quit
[RouterB] interface ethernet 1/1
[RouterB-Ethernet1/1] pim dm
[RouterB-Ethernet1/1] igmp enable
[RouterB-Ethernet1/1] igmp static-group 224.0.1.1
4 Configuration on Router A:
# Enable IP multicast routing and IGMP.
<RouterA> system-view
[RouterA] multicast routing-enable
[RouterA] interface ethernet 1/0
[RouterA-Ethernet1/0] igmp enable
[RouterA-Ethernet1/0] igmp static-group 224.0.1.1
# Configure Router A to work in the multicast client mode and receive multicast
messages on Ethernet 1/0.
[RouterA-Ethernet1/0] ntp-service multicast-client
# View the NTP status of Router A after clock synchronization.
[RouterA-Ethernet1/0] display ntp-service status
Clock status: synchronized
Clock stratum: 3
Reference clock ID: 3.0.1.31
Nominal frequency: 64.0000 Hz
Actual frequency: 64.0000 Hz
Clock precision: 2^7
Clock offset: 0.0000 ms
Root delay: 40.00 ms
Root dispersion: 10.83 ms
Peer dispersion: 34.30 ms
Reference time: 16:02:49.713 UTC Sep 19 2005 (C6D95F6F.B6872B02)
As shown above, Router A has been synchronized to Router C and the clock
stratum level of Router A is 3, while that of Router C is 2.
# View the NTP session information of Router A, which shows that an association
has been set up between Router A and Router C.
[RouterA] display ntp-service sessions
source reference
**************************************************************************
[1234] 3.0.1.31 127.127.1.0
note: 1 source(master),2 source(peer),3 selected,4 candidate,5 configured
Total associations :
stra reach poll
2 255 64
1
NTP Configuration Examples
now offset delay
26 -16.0 40.0 16.6
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disper