ZyXEL Communications MES3500-24, User Manual

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Chapter 26 IP Source Guard
MES3500-24/24F User’s Guide
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26.5 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 77
DHCP Snooping (continued)
LABEL DESCRIPTION