3Com 5500-SI Configuration Manual page 496

496 C 22: F S
HAPTER ILE YSTEM
M
ANAGEMENT
Configuring NTP Broadcast Client Mode
Designate an interface on the local Switch to receive NTP broadcast messages and
operate in broadcast client mode. The local Switch listens to the broadcast from the
server. When it receives the first broadcast packets, it starts a brief client/server mode
to Switch messages with a remote server for estimating the network delay. Thereafter,
the local Switch enters broadcast client mode and continues listening to the
broadcast and synchronizes the local clock according to the arrived broadcast
message.
Perform the following configurations in the VLAN Interface View.
Table 566 Configure NTP Broadcast Client Mode
Operation
Configure NTP broadcast client mode
Disable NTP broadcast client mode
This command can only be configured on the interface where the NTP broadcast
packets will be received.
Configuring NTP Multicast Server Mode
Designate an interface on the local Switch to transmit NTP multicast packets. In this
case, the local equipment operates in multicast mode and serves as a multicast server
to multicast messages to its clients regularly.
Perform the following configurations in the VLAN Interface View.
Table 567 Configure NTP Multicast Server Mode
Operation
Configure NTP multicast server
mode
Cancel NTP multicast server mode undo ntp-service multicast-server
NTP version number
key ID ranges from 0 to 4294967295;
keyid
ranges from 1 to 255; and the multicast IP address defaults to 224.0.1.1.
This command can only be configured on the interface where the NTP multicast
packet will be transmitted.
Configuring NTP Multicast Client Mode
Designate an interface on the local Switch to receive NTP multicast messages and
operate in multicast client mode. The local Switch listens to the multicast from the
server. When it receives the first multicast packets, it starts a brief client/server mode
to Switch messages with a remote server for estimating the network delay. Thereafter,
the local Switch enters multicast client mode and continues listening to the multicast
and synchronizes the local clock by the arrived multicast message.
Perform the following configurations in VLAN interface view.
Table 568 Configure NTP multicast client mode
Operation
Configure NTP multicast client
mode
Cancel NTP multicast client mode
Command
ntp-service broadcast-client
undo ntp-service broadcast-client
Command
ntp-service multicast-server [ ip-address ] [
authentication-keyid keyid ] [ ttl ttl-number
] [ version number ]
ranges from 1 to 3 and defaults to 3; the authentication
number
Command
ntp-service multicast-client [ ip-address ]
undo ntp-service multicast-client
of the multicast packets
ttl-number