6-38
Catalyst 3550 Multilayer Switch Software Configuration Guide
78-11194-03
Chapter 6 Administering the Switch
Managing the System Time and Date
To disable the interface from sending NTP broadcast packets, use the no ntp broadcast interface
configuration command.
This example shows how to configure an interface to send NTP version 2 packets:
Switch(config)# interface gigabitethernet0/1
Switch(config-if)# ntp broadcast version 2
Beginning in privileged EXEC mode, follow these steps to configure the switch to receive NTP
broadcast packets from connected peers:
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 an interface to receive NTP broadcast packets:
Switch(config)# interface gigabitethernet0/1
Switch(config-if)# ntp broadcast client
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 6-39
•
Disabling NTP Services on a Specific Interface, page 6-40
Step 6
copy running-config startup-config
(Optional) Save your entries in the configuration file.
Step 7
Configure the connected peers to receive NTP broadcast packets as
described in the next procedure.
Command
Purpose
Command
Purpose
Step 1
configure terminal
Enter global configuration mode.
Step 2
interface interface-id
Enter interface configuration mode, and specify the interface to receive
NTP broadcast packets.
Step 3
ntp broadcast client
Enable the interface to receive NTP broadcast packets.
By default, no interfaces receive NTP broadcast packets.
Step 4
exit
Return to global configuration mode.
Step 5
ntp broadcastdelay microseconds
(Optional) Change 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
Return to privileged EXEC mode.
Step 7
show running-config
Verify your entries.
Step 8
copy running-config startup-config
(Optional) Save your entries in the configuration file.