3Com Switch 7750 Configuration Guide

758 CHAPTER 70: NTP CONFIGURATION
NTP client mode
When a Switch 7750 operates in the NTP client mode,
■ The remote server identified by the remote-ip argument operates as the NTP
time server. The Switch 7750 operates as the client, whose clock is
synchronized to the NTP server. (In this case, the clock of the NTP server is not
synchronized to the local client.)
■ When the remote-ip argument is an IP address of a host, it cannot be a
broadcast or a multicast address, neither can it be the IP address of a reference
clock.
NTP peer mode
When a Switch 7750 operates in NTP peer mode,
■ The remote server identified by the remote-ip argument operates as the peer of
the Switch 7750, and the Switch 7750 operates as the active peer. The clock of
the Switch 7750 can be synchronized to the remote server or be used to
synchronize the clock of the remote server.
■ When the remote-ip argument is an IP address of a host, it cannot be a
broadcast or a multicast address, neither can it be the IP address of a reference
clock.
NTP broadcast server mode
When a Switch 7750 operates in NTP broadcast server mode, it broadcasts a clock
synchronization packet periodically. The devices which are configured to be in the
NTP broadcast client mode will respond this packet and start the clock
synchronization procedure.
NTP multicast server mode
When a Switch 7750 operates in NTP multicast server mode, it multicasts a clock
synchronization packet periodically. The devices which are configured to be in the
Enter VLAN interface
view
interface interface -type
interface-number
-
Configure to operate
in the NTP broadcast
client mode
ntp-service broadcast-client Optional
By default, no Ethernet switch
operates in the NTP broadcast
client mode
Configure to operate
in the NTP broadcast
server mode
ntp-service broadcast-server
[ authentication-keyid key-id |
version number ]*
Optional
By default, no Ethernet switch
operates in the NTP broadcast
server mode
Configure to operate
in the NTP multicast
client mode
ntp-service multicast-client
[ ip-address ]
Optional
By default, no Ethernet switch
operates in the NTP multicast
client mode
Configure to operate
in the NTP multicast
server mode
ntp-service multicast-server
[ ip-address ]
[ authentication-keyid keyid |
ttl ttl-number | version
number ]*
Optional
By default, no Ethernet switch
operates in the NTP multicast
server mode
Table 602 Configure NTP implementation modes
Operation Command Description