Table 184: DHCP Snooping Interface Configuration Fields
Field
Description
Interface
The interface associated with the rest of the data in the row. When configuring
the settings for one or more interfaces, this field identifies each interface that is
being configured.
Trust State
The trust state configured on the interface. The trust state is one of the following:
•
Disabled – The interface is considered to be untrusted and could potentially
be used to launch a network attack. DHCP server messages are checked
against the bindings database. On untrusted ports, DHCP snooping enforces
the following security rules:
•
DHCP packets from a DHCP server (DHCPOFFER, DHCPACK, DHCPNAK,
DHCPRELEASEQUERY) are dropped.
•
DHCPRELEASE and DHCPDECLINE messages are dropped if the MAC
address is in the snooping database but the binding's interface is other
than the interface where the message was received.
•
DHCP packets are dropped when the source MAC address does not
match the client hardware address if MAC Address Validation is globally
enabled.
•
Enabled – The interface is considered to be trusted and forwards DHCP
server messages without validation.
Log Invalid Packets
The administrative mode of invalid packet logging on the interface. When
enabled, the DHCP snooping feature generates a log message when an invalid
packet is received and dropped by the interface.
Rate Limit (pps)
The rate limit value for DHCP packets received on the interface. To prevent DHCP
packets from being used as a DoS attack when DHCP snooping is enabled, the
snooping application enforces a rate limit for DHCP packets received on
untrusted interfaces. If the incoming rate of DHCP packets exceeds the value of
this object during the amount of time specified for the burst interval, the port
will be shutdown. You must administratively enable the port to allow it to resume
traffic forwarding.
Burst Interval (Seconds)
The burst interval value for rate limiting on this interface. If the rate limit is
unspecified, then burst interval has no meaning.
Click
Refresh
to refresh the page with the most current data from the switch.
DHCP Snooping Static Bindings
Use the DHCP Snooping Static Bindings page to view, add, and remove static bindings in the
snooping bindings database.
To access this page, click
Switching
>
DCHP Snooping
>
Base
>
Static Bindings
in the navigation
menu.
Table 185: DHCP Snooping Static Bindings Fields
Field
Description
Interface
The interface on which the DHCP client is authorized.
MAC Address
The MAC address associated with the DHCP client. This is the Key to the binding
database.
Configuring Switching Information
ExtremeSwitching 200 Series: Administration Guide
191