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Chapter 24 IP Source Guard
XS3900-48F User’s Guide
209
24.5 DHCP Snooping Configure
Use this screen to enable DHCP snooping on the Switch (not on specific VLAN), specify the VLAN
where the default DHCP server is located, and configure the DHCP snooping database. The DHCP
snooping database stores the current bindings on a secure, external TFTP server so that they are
Last ignored bindings
counters
This section displays the number of times and the reasons the Switch ignored
bindings the last time it read bindings from the DHCP binding database. You can
clear these counters by restarting the Switch or using CLI commands. See the
Ethernet Switch CLI Reference Guide.
Binding collisions
This field displays the number of bindings the Switch ignored because the Switch
already had a binding with the same MAC address and VLAN ID.
Invalid interfaces
This field displays the number of bindings the Switch ignored because the port
number was a trusted interface or does not exist anymore.
Parse failures
This field displays the number of bindings the Switch ignored because the Switch
was unable to understand the binding in the DHCP binding database.
Expired leases
This field displays the number of bindings the Switch ignored because the lease
time had already expired.
Unsupported vlans
This field displays the number of bindings the Switch ignored because the VLAN ID
does not exist anymore.
Last ignored time
This field displays the last time the Switch ignored any bindings for any reason
from the DHCP binding database.
Total ignored bindings
counters
This section displays the reasons the Switch has ignored bindings any time it read
bindings from the DHCP binding database. You can clear these counters by
restarting the Switch or using CLI commands. See the Ethernet Switch CLI
Reference Guide.
Binding collisions
This field displays the number of bindings the Switch has ignored because the
Switch already had a binding with the same MAC address and VLAN ID.
Invalid interfaces
This field displays the number of bindings the Switch has ignored because the port
number was a trusted interface or does not exist anymore.
Parse failures
This field displays the number of bindings the Switch has ignored because the
Switch was unable to understand the binding in the DHCP binding database.
Expired leases
This field displays the number of bindings the Switch has ignored because the lease
time had already expired.
Unsupported vlans
This field displays the number of bindings the Switch has ignored because the VLAN
ID does not exist anymore.
Table 85
DHCP Snooping (continued)
LABEL
DESCRIPTION