3Com 5500 SI - Switch - Stackable, Configuration Manual

Page: 496 / 686

496 C
HAPTER
22: F
ILE
S
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
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
NTP version number
number
ranges from 1 to 3 and defaults to 3; the authentication
key ID
keyid
ranges from 0 to 4294967295;
ttl-number
of the multicast packets
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 Command
Configure NTP broadcast client mode
ntp-service broadcast-client
Disable NTP broadcast client mode
undo ntp-service broadcast-client
Operation Command
Configure NTP multicast server
mode
ntp-service multicast-server [ ip-address ] [
authentication-keyid keyid ] [ ttl ttl-number
] [ version number ]
Cancel NTP multicast server mode
undo ntp-service multicast-server
Operation Command
Configure NTP multicast client
mode
ntp-service multicast-client [ ip-address ]
Cancel NTP multicast client mode
undo ntp-service multicast-client