3Com 7700 Configuration Manual page 317

Configuring NTP Operating Mode
S3026 and S2403H Ethernet Switches can only serve as ntp client but not ntp
server.
You can set the NTP operating mode of an Ethernet Switch according to its
location in the network and the network structure. For example, you can set a
remote server as the time server of the local equipment. In this case the local
Ethernet Switch works as an NTP client. If you set a remote server as a peer of the
local Ethernet Switch, the local equipment operates in symmetric active mode. If
you configure an interface on the local Ethernet Switch to transmit NTP broadcast
packets, the local Ethernet Switch will operates in broadcast mode. If you
configure an interface on the local Ethernet Switch to receive NTP broadcast
packets, the local Ethernet Switch will operates in broadcast client mode. If you
configure an interface on the local Ethernet Switch to transmit NTP multicast
packets, the local Ethernet Switch will operates in multicast mode. Or you may
also configure an interface on the local Ethernet Switch to receive NTP multicast
packets, the local Ethernet Switch will operates in multicast client mode.
Configuring NTP Server Mode
■
Configuring NTP Peer Mode
■
Configuring NTP Broadcast Server Mode
■
Configuring NTP Broadcast Client Mode
■
Configuring NTP Multicast Server Mode
■
Configuring NTP Multicast Client Mode
■
Configuring NTP Server Mode
ip-address as the local time server. ip-address specifies a host address other than a
broadcast, multicast or reference clock IP address. In this case, the local switch
operates in client mode. In this mode, only the local client synchronizes its clock
with the clock of the remote server, while the reverse synchronization will not
happen.
Perform the following configurations in system view.
Table 65 Configure NTP Time Server
Operation
Configure NTP time server
Cancel NTP 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; interface-name or
interface-type interface-number specifies the IP address of an interface, from
which the source IP address of the NTP packets sent from the local switch to the
time server will be taken; priority indicates the time server will be the first choice.
Configuring NTP Peer Mode
ip-address as the peer of the local equipment. In this case, the local equipment
operates in symmetric active mode. ip-address specifies a host address other than
Set a remote server whose IP address is
Command
ntp-service unicast-server ip-address [
version number ] [ authentication-keyid
keyid ] [ source-interface { interface-name |
interface-type interface-number } ] [ priority ]
undo ntp-service unicast-server ip-address
Set a remote server whose IP address is
NTP 37