Ip Dhcp Snooping Database - Cisco Catalyst 3750 Command Reference Manual

Chapter 2 Catalyst 3750 Switch Cisco IOS Commands
Usage Guidelines
The DHCP snooping binding database can have up to 512 bindings.
To ensure that the lease time in the database is accurate, we recommend that Network Time Protocol
(NTP) is enabled and configured for these features:
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If NTP is not configured, the switch writes binding changes to the binding file only when the switch
system clock is synchronized with NTP.
Because both NVRAM and the flash memory have limited storage capacity, we recommend that you
store a binding file on a TFTP server. You must create an empty file at the configured URL on
network-based URLs (such as TFTP and FTP) before the switch can write bindings to the binding file at
that URL for the first time.
Use the ip dhcp snooping database flash[number]:/filename command to save the DHCP snooping
binding database in the stack master NVRAM. The database is not saved in a stack member NVRAM.
Use the no ip dhcp snooping database command to delete the agent or file specified by the URL.
Use the no ip dhcp snooping database timeout command to reset the timeout value.
Use the no ip dhcp snooping database write-delay command to reset the write-delay value.
Examples
This example shows how to store a binding file at an IP address of 10.1.1.1 that is in a directory called
directory. A file named file must be present on the TFTP server.
Switch(config)# ip dhcp snooping database tftp://10.1.1.1/directory/file
This example shows how to store a binding file called file01.txt in the stack master NVRAM.
Switch(config)# ip dhcp snooping database flash:file01.text
You can verify your settings by entering the show ip dhcp snooping database privileged EXEC
command.
Related Commands Command
ip dhcp snooping
ip dhcp snooping binding
show ip dhcp snooping database
78-16181-03
NTP authentication
NTP peer and server associations
NTP broadcast service
NTP access restrictions
NTP packet source IP address
Description
Enables DHCP snooping on a VLAN.
Configures the DHCP snooping binding database.
Displays the status of DHCP snooping database agent.
Catalyst 3750 Switch Command Reference

ip dhcp snooping database

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