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Catalyst 4500 Series Switch, Cisco IOS Software Configuration Guide - Cisco IOS XE 3.9.xE and IOS 15.2(5)Ex
Chapter 4 Administering the Switch
Managing the System Time and Date
To configure the switch to receive NTP broadcast packets from connected peers, perform this task:
To disable an interface from receiving NTP broadcast packets, use the
no ntp broadcast client
interface
configuration command. To change the estimated round-trip delay to the default, use the
no ntp broadcastdelay
global configuration command.
This example shows how to configure a port to receive NTP broadcast packets:
Switch#
configure terminal
Switch(config)#
interface gigabitethernet0/1
Switch(config-if)#
ntp broadcast client
Switch(config-if)#
end
Switch#
Configuring NTP Access Restrictions
You can control NTP access on two levels as described in these sections:
•
Creating an Access Group and Assigning a Basic IP Access List, page 4-9
•
Disabling NTP Services on a Specific Interface, page 4-10
Command
Purpose
Step 1
configure terminal
Enters global configuration mode.
Step 2
interface
interface-id
Specifies the interface to receive NTP broadcast packets, and enter
interface configuration mode.
Step 3
ntp broadcast client
Enables the interface to receive NTP broadcast packets.
By default, no interfaces receive NTP broadcast packets.
Step 4
exit
Returns to global configuration mode.
Step 5
ntp broadcastdelay
microseconds
(Optional) Changes the estimated round-trip delay between the switch and
the NTP broadcast server.
The default is 3000 microseconds; the range is 1 to 999999.
Step 6
end
Returns to privileged EXEC mode.
Step 7
show running-config
Verifies your entries.
Step 8
copy running-config startup-config
(Optional) Saves your entries in the configuration file.
Summary of Contents for Catalyst 4500 Series
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