Cisco Catalyst 4500 Series Command Reference Guide

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Catalyst 4500 Series Switch Cisco IOS Command Reference—Release IOS XE 3.4.0SG and IOS 15.1(2)SG)
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Chapter 2 Cisco IOS Commands for the Catalyst 4500 Series Switches
ip dhcp snooping database
ip dhcp snooping database
To store the bindings that are generated by DHCP snooping, use the ip dhcp snooping database
command. To either reset the timeout, reset the write-delay, or delete the agent specified by the URL,
use the no form of this command.
ip dhcp snooping database {url | timeout seconds | write-delay seconds}
no ip dhcp snooping database {timeout | write-delay}
Syntax Description
Defaults The timeout value is set to 300 seconds (5 minutes).
The write-delay value is set to 300 seconds.
Command Modes Interface configuration mode
Command History
Usage Guidelines You need to create an empty file at the configured URL on network-based URLs (such as TFTP and FTP)
before the switch can write the set of bindings for the first time at the URL.
Note Because both NVRAM and bootflash have limited storage capacity, using TFTP or network-based files
is recommended . If you use flash to store the database file, new updates (by the agent) result in the
creation of new files (flash fills quickly). In addition, due to the nature of the file system used on the
flash, a large number of files causes access to be considerably slowed. When a file is stored in a remote
location accessible through TFTP, an RPR/SSO standby supervisor engine can take over the binding list
when a switchover occurs.
url Specifies the URL in one of the following forms:
• tftp://<host>/<filename>
• ftp://<user>:<password>@<host>/<filename>
• rcp://<user>@<host>/<filename>
• nvram:/<filename>
• bootflash:/<filename>
timeout seconds Specifies when to abort the database transfer process after a change to the binding
database.
The minimum value of the delay is 15 seconds. 0 is defined as an infinite duration.
write-delay
seconds
Specifies the duration for which the transfer should be delayed after a change to
the binding database.
Release Modification
12.1(19)EW Support for this command was introduced on the Catalyst 4500 series switch.

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