xStack
®
DGS-3400 Series Layer 2 Gigabit Managed Switch CLI Manual
147
Example usage:
To disable IMPB debugging on the Switch:
D G S – 3 4 2 6 : 5 # n o d e b u g a d d r e s s _ b i n d i n g
C o m m a n d : n o d e b u g a d d r e s s _ b i n d i n g
S u c c e s s .
D G S – 3 4 2 6 : 5 #
enable address_binding dhcp_snoop
Purpose
To enable the DHCP snooping option for IMPB.
Syntax
enable address_binding dhcp_snoop
Description
If DHCP snooping is enabled, the Switch learns IP-MAC pairs by snooping DHCP
packets automatically and then saves them to the IP-MAC-Port Binding white list. This
enables a hassle-free configuration because the administrator does not need to manually
enter each IMPB entry. A prerequisite for this is that the valid DHCP server’s IP-MAC pair
must be configured on the Switch’s IMPB while list first; otherwise the DHCP server
packets will be dropped. DHCP snooping is generally considered to be more secure
because it enforces all clients to acquire IP through the DHCP server. Additionally, it
makes IP Information auditable because clients cannot manually configure their own IP
address.
Each DHCP-snooped entry is associated with a lease time. When the lease time expires,
the expired entry will be removed from this port. The auto-learned binding entry can be
moved from one port to another port if the DHCP snooping function has learned that the
MAC address is moved to a different port.
In order to avoid conflict where both static entry and DHCP Snooping entry are the same,
DHCP Snooping entries will not be created if the IP-MAC entry has already been
statically configured.
Parameters None.
Restrictions
Only Administrator and Operator-level users can issue this command.
Example usage:
To enable the address binding auto mode:
D G S – 3 4 2 6 : 5 # e n a b l e a d d r e s s _ b i n d i n g d h c p _ s n o o p
C o m m a n d : e n a b l e a d d r e s s _ b i n d i n g d h c p _ s n o o p
S u c c e s s .
D G S – 3 4 2 6 : 5 #
