Ntp Configuration; Configuring Ntp Operating Mode - H3C S9500 Series Operation Manual

Operation Manual – System Management
H3C S9500 Series Routing Switches
Now Ethernet Switch A collects enough information to calculate the following two
important parameters:
The delay for a round trip of an NTP packet traveling between the Switch A and B:
Delay= (T
Offset of Ethernet Switch A clock relative to Ethernet Switch B clock: offset=
( (T
2
In this way, Ethernet Switch A uses the above information to set the local clock and
synchronize it with the clock on Ethernet Switch B.
The operating principle of NTP is briefly introduced above. For details, refer to
RFC1305.

7.2 NTP Configuration

NTP is used for time synchronization throughout a network. The following sections
describe the NTP configuration tasks.

Configuring NTP Operating Mode

Configuring NTP ID Authentication
Setting NTP Authentication Key
Setting Specified Key as Reliable
Designating an Interface to Transmit NTP Messages
Setting NTP Master Clock
Setting Authority to Access a Local Ethernet Switch
Setting Maximum Local Sessions
7.2.1 Configuring NTP Operating Mode
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 operate in Multicast Client mode.
Configure NTP server mode
Configure NTP peer mode
Configure NTP broadcast server mode
Configure NTP broadcast client mode
-T ) - (T -T ).
4 1 3 2
-T ) + (T -T ) ) /2.
1 4 3
7-3
Chapter 7 NTP Configuration