Cisco Catalyst 4500 Series Software Configuration Guide

4-10
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 remove access control to the switch NTP services, use the
no ntp access-group {query-only | serve-only | serve | peer} global configuration command.
This example shows how to configure the switch to allow itself to synchronize to a peer from access
list 99. However, the switch restricts access to allow only time requests from access list 42:
Switch# configure terminal
Switch(config)# ntp access-group peer 99
Switch(config)# ntp access-group serve-only 42
Switch(config)# access-list 99 permit 172.20.130.5
Switch(config)# access list 42 permit 172.20.130.6
Switch(config)# end
Switch#
Disabling NTP Services on a Specific Interface
NTP services are enabled on all interfaces by default.
To disable NTP packets from being received on an interface, perform this task:
Configuring the Source IP Address for NTP Packets
When the switch sends an NTP packet, the source IP address is normally set to the address of the
interface through which the NTP packet is sent. To use a particular source IP address for all NTP packets,
use the ntp source global configuration command. The address is taken from the specified interface.
This command is useful if the address on an interface cannot be used as the destination for reply packets.
To configure a specific interface from which the IP source address is to be taken, perform this task:
Command Purpose
Step 1
configure terminal
Enters global configuration mode.
Step 2
interface interface-id
Enters interface configuration mode, and specify the interface to disable.
Step 3
ntp disable
Disables NTP packets from being received on the interface.
By default, all interfaces receive NTP packets.
To reenable receipt of NTP packets on an interface, use the
no ntp disable interface configuration command.
Step 4
end
Returns to privileged EXEC mode.
Step 5
show running-config
Verifies your entries.
Step 6
copy running-config startup-config
(Optional) Saves your entries in the configuration file.
Command Purpose
Step 1
configure terminal
Enters global configuration mode.
Step 2
ntp source type number
Specifies the interface type and number from which the IP source address
is taken.
By default, the source address is set by the outgoing interface.
Step 3
end
Returns to privileged EXEC mode.
Step 4
show running-config
Verifies your entries.
Step 5
copy running-config startup-config
(Optional) Saves your entries in the configuration file.

Cisco Catalyst 4500 Series Specifications

General

Series	Catalyst 4500 Series
Category	Switch
Layer Support	Layer 2, Layer 3
Form Factor	Modular chassis
Stackable	No
Chassis Slots	3, 6, 7, 10
Power Supply Options	AC, DC
Redundancy	Power supply, Supervisor engine
Network Management	Cisco IOS Software CLI, SNMP, Cisco Prime Infrastructure
Features	Security, QoS
Port Density	Up to 384 ports per chassis
Security Features	802.1X, ACLs, DHCP Snooping, Dynamic ARP Inspection, IP Source Guard
Supervisor Engine	8-E