R3166-R3206-HP High-End Firewalls System Management and Maintenance Configuration Guide-6PW101

NOTE:

• A CE is a device that has an interface directly connecting to the service provider (SP). A CE is not

“aware of” the presence of the VPN.

• A PE is a device directly connecting to CEs. In a network, all events related to VPN processing occu

on the PE.

NTP configuration task list

Complete the following tasks to configure NTP:

Task Remarks

Configuring the operation modes of NTP Required

Configuring the local clock as a reference source Optional

Configuring optional parameters of NTP Optional

Configuring access-control rights Optional

Configuring NTP authentication Optional

Configuring the operation modes of NTP

Devices can implement clock synchronization in one of the following modes:

• Client/server mode

• Symmetric mode

• Broadcast mode

• Multicast mode

For the client/server mode or symmetric mode, you need to configure only clients or symmetric-active

peers; for the broadcast or multicast mode, you need to configure both servers and clients.

NOTE:

sin

le device can have a maximum of 128 associations at the same time, includin

static associations

and dynamic associations. A static association refers to an association that a user has manually created

by usin

an NTP command, while a dynamic association is a temporary association created by the system

during operation. A dynamic association will be removed if the system fails to receive messages from it

over a specific long time. In the client/server mode, for example, when you carry out a command to

synchronize the time to a server, the system will create a static association, and the server will just respond

passively upon the receipt of a message, rather than creating an association (static or dynamic). In the

symmetric mode, static associations will be created at the symmetric-active peer side, and dynamic

associations will be created at the symmetric-passive peer side; in the broadcast or multicast mode, static

associations will be created at the server side, and dynamic associations will be created at the client side.

Configuring NTP client/server mode

For devices working in the client/server mode, you only need to make configurations on the clients, but

not on the servers.

Follow these steps to configure an NTP client: