Users Guide

Layer 2 Switching Commands 382
ipv6 dhcp snooping database
Use the ipv6 dhcp snooping database command to configure the persistent
location of the DHCP snooping database. This can be a local or remote file
on a TFTP server.
Syntax
ipv6 dhcp snooping database {local | tftp://hostIP/filename}
no ipv6 dhcp snooping database
Default Configuration
By default, the local database is used.
Command Modes
Global Configuration mode
User Guidelines
The DHCP binding database is persistently stored on a configured external
server or locally in flash, depending on the user configuration. A row-wise
checksum is placed in the text file that is stored on the configured TFTP
server. On switch startup, the switch reads the text file and uses the contents
to build the DHCP snooping database. If the calculated checksum value
equals the stored checksum, the switch uses the entries from the binding file
and populates the binding database. Checksum failure or a connection
problem to the external configured server causes the switch to lose the
bindings and may cause connectivity loss for hosts if IPSG or DAI is enabled.
ipv6 dhcp snooping database write-delay
Use the ipv6 dhcp snooping database write-delay command to configure the
time period between successive writes of the binding database. The binding
database is used to persistently store the DHCP bindings. Use the no form of
the command to return the write delay to the default value.
Syntax
ipv6 dhcp snooping database write-delay seconds