Configuring Ntp Access Control Authority - Huawei AR150 Series Configuration Manual

Huawei AR150&200&1200&2200&3200 Series Enterprise
Routers
Configuration Guide - Device Management

5.5.4.3 Configuring NTP Access Control Authority

Context
NTP access control is a simple security measure. When an access request reaches the local end,
the access request is successively matched with the access authority from the maximum one to
the minimum one. The first successfully matched access authority takes effect. The matching
order is: peer, server, synchronization, and query.
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l
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The access control authority is configured on different devices in different NTP operating modes,
as described in
Table 5-3 Configuration of the NTP access control authority
NTP Operating
Mode
Unicast NTP client/
server mode
Unicast NTP client/
server mode
NTP symmetric peer
mode
NTP symmetric peer
mode
NTP multicast mode The client is restricted from
NTP broadcast
mode
Issue 05 (2014-01-16)
peer: indicates the maximum access authority. The remote end can perform time requests
and control queries for the local NTP service. The local clock can also be synchronized
with the clock of the remote server.
server: indicates that the remote end can send a time request and a control query to the
local end. The local clock, however, cannot be synchronized with the clock of the remote
server.
synchronization: indicates that the remote end can perform only the time request to the
local end.
query: indicates the minimum access authority. The remote end can only perform the
control query to the local end.
Table 5-3.
Restricted NTP Request
Type
The client is restricted from
synchronizing to the server.
The server is restricted from
processing the clock
synchronization request sent
by the client.
A symmetric passive peer and
a symmetric active peer are
restricted from synchronizing
with each other.
The symmetric passive peer is
restricted from processing the
clock request sent by the
symmetric active peer.
synchronizing to the server.
The client is restricted from
synchronizing to the server.
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5 NTP Configuration
Configured Device
Client
Server
Symmetric active peer
Symmetric passive peer
NTP multicast client
NTP broadcast client
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