3com 8807 Reference Guide

C

HAPTER

 55: NTP C

ONFIGURATION

 C

OMMANDS

By default, a local device allows up to 100 SESSIONS.

# Set the local equipment to allow up to 50 SESSIONS.

<SW8800> system-view

 

System View: return to User View with Ctrl+Z.

 

[SW8800] ntp-service max-dynamic-sessions 50 

ntp-service multicast-client [ ip-address ]

undo ntp-service multicast-client [ ip-address ]

VLAN interface view

ip-address: Multicast IP address of Class D. By default, the ip-address argument is 
set to 224.0.1.1. Actually, for the Switch 8800 Family series, you can set 224.0.1.1 
as the multicast IP address only.

Use the ntp-service multicast-client command to configure the NTP multicast 
client mode.

Use the undo ntp-service multicast-client command to disable the NTP 
multicast client mode.

By default, the multicast client service is disabled. ip-address defaults to 224.0.1.1.

Designate an interface on the local Ethernet Switch to receive NTP multicast 
messages and operate in Multicast Client mode. The local Ethernet Switch listens 
to the multicast packets from the server. When it receives the first multicast 
packet, it starts a brief Client/Server mode to switch messages with a remote 
server for estimating the network delay. Thereafter, the local Ethernet Switch 
enters Multicast Client mode and continues listening to the multicast packets and 
synchronizes the local clock according to the arrived multicast packets.

# Configure to receive NTP multicast packet through Vlan-Interface1 and the 
multicast group corresponding to these packets located at 224.0.1.1.

<SW8800> system-view

 

System View: return to User View with Ctrl+Z.

 

[SW8800] interface vlan-interface 1

 

[3Com-Vlan-interface1] ntp-service multicast-client 224.0.1.1 

ntp-service multicast-server [ ip-address ] [ authentication-keyid keyid ] [ ttl 
ttl-number ] [ version number ]*

undo ntp-service multicast-server [ ip-address ]