Ip Dhcp Snooping Database - Cisco Catalyst 4500 Series Command Reference Manual

Chapter 2 Cisco IOS Commands for the Catalyst 4500 Series Switches

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.
Syntax Description
url
timeout seconds
write-delay
seconds
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 Release
12.1(19)EW
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.
Because both NVRAM and bootflash have limited storage capacity, using TFTP or network-based files
Note
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.
OL-27596 -01
ip dhcp snooping database {url | timeout seconds | write-delay seconds}
no ip dhcp snooping database {timeout | write-delay}
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>
•
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.
Specifies the duration for which the transfer should be delayed after a change to
the binding database.
Modification
Support for this command was introduced on the Catalyst 4500 series switch.
Catalyst 4500 Series Switch Cisco IOS Command Reference—Release IOS XE 3.4.0SG and IOS 15.1(2)SG)
ip dhcp snooping database
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