3Com 7750 Series Command Reference Manual page 936

3Com Switch 7750 Series
Command Reference Guide – NTP
undo ntp-service access { query | synchronization | server | peer }
View
System view
Parameter
query: Allows to query the local NTP service only.
synchronization: Only allows the peer device to synchronize its clock to the local
device..
server: Allows the peer device to perform synchronization and control query to the
local device but does not permit the local device to synchronize its clock to the peer
device.
peer: Full access. This level of right permits the peer device to perform
synchronization and control query to the local device and also permits the local device
to synchronize its clock to the peer device.
acl-number: The IP address access control list number, ranging from 2000 to 2999.
Description
Use the ntp-service access command to set the right to access the local device
service.
Use the undo ntp-service access command to cancel the access authority settings.
By default, no right limit is configured.
Compared with authentication, setting the right to access and control the NTP services
is a basic and brief security measure. From the highest NTP service access-control
right to the lowest one are peer, server, synchronization, and query. When a device
receives an NTP request, it will perform an access control right match and will used
first matched right..
Example
# Configure to permit the remote switch defined in ACL 2000 to perform time
synchronization request, query and synchronization to the local device..
<3Com> system-view
System View: return to User View with Ctrl+Z.
[3Com] ntp-service access peer 2000
# Configure to permit the remote switch defined in ACL 2000 to perform time
synchronization request and query to the local device.
<3Com> system-view
System View: return to User View with Ctrl+Z.
[3Com] ntp-service access synchronization 2000
Chapter 1 NTP Configuration Commands
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