Command: show address_binding ip_mac all
M(Mode) - D:DHCP, N:ND S:Static ACL - A:Active I:Inactive
IP Address MAC Address M ACL Ports
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10.1.1.1 00-00-00-00-00-11 S I 1:1-1:24
Total Entries : 1
43-11 enable address_binding dhcp_snoop
Description
This command is used to enable DHCP snooping mode.
By default, DHCP snooping is disabled.
When a user enables the DHCP snooping mode, DHCPv4 snooping can learn binding entries only
on IMPB enabled ports. DHCPv6 snooping can learn binding entries on all ports whether the port
is IMPB enabled or disabled. DHCP server packets (both DHCPv4 and DHCPv6) received from
IMPB enabled ports, must be verified before they are forwarded out. If the source IP address is not
found in the binding table, it will be dropped.
NOTE: The DHCP discover packets cannot be passed thru the user ports if the allow_zeroip
function is disabled on the port.
The auto-learned IMPB entry will be mapped to a specific source port based on the MAC address
learning function. This entry will be created as an IP-Inspection mode binding entry for this specific
port. Each entry is associated with a lease time. When the lease time has expires, the expired
entry will be removed from the 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 has moved to a
different port.
If a situation occurs where a binding entry learned by DHCP snooping conflicts with a statically
configured entry. The binding relation has conflicted. For example, if IP A is binded to MAC X with
a static configuration and suppose that the binding entry learned by DHCP snooping is that IP A is
bound to MAC Y, and then it is conflict. When the DHCP snooping learned entry binds with the
static configured entry, and the DHCP snooping learned entry will not be created.
In a situation where the same IMPB pair has been statically configured, the auto-learned entry will
not be created. In a situation where the learned information is consistent with the statically
configured entry the auto-learned entry will not be created. In a situation where the entry is
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