H3C Technologies H3C WX6000 Series Access Controllers - Manual (Page 87)

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[AC3-Vlan-interface2] ntp-service broadcast-client
3) Configuration on AC 1:
# Configure AC 1 to work in the broadcast client mode and receive broadcast messages on
VLAN-interface 3.
system-view
[AC1] interface vlan-interface 3
[AC1-Vlan-interface3] ntp-service broadcast-client
Because AC 1 and AC 2 are on different subnets, AC 1 cannot receive the broadcast messages from
AC 2. AC 3 gets synchronized upon receiving a broadcast message from AC 2.
# View the NTP status of AC 3 after clock synchronization.
[AC3-Vlan-interface2] 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: 31.00 ms
Root dispersion: 8.31 ms
Peer dispersion: 34.30 ms
Reference time: 16:01:51.713 UTC Sep 19 2005 (C6D95F6F.B6872B02)
As shown above, AC 3 has been synchronized to AC 2, and the clock stratum level of AC 3 is 3, while
that of AC 2 is 2.
# View the NTP session information of AC 3, which shows that an association has been set up between
AC 3 and AC 2.
[AC3-Vlan-interface2] display ntp-service sessions
source reference stra reach poll now offset delay disper
**************************************************************************
[1234] 3.0.1.31 127.127.1.0 2 254 64 62 -16.0 32.0 16.6
note: 1 source(master),2 source(peer),3 selected,4 candidate,5 configured
Total associations : 1
Configuring NTP Multicast Mode
Network requirements
z The local clock of AC 2 is to be used as a reference source, with the stratum level of 2.
z AC 2 works in the multicast server mode and sends out multicast messages from VLAN-interface
2.
z AC 1 and AC 3 work in the multicast client mode and receive multicast messages through
VLAN-interface 3 and VLAN-interface 2 respectively.