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ONFIGURING
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DHCP S
FOR
NOOPING
DHCP Snooping Status – Enables or disables DHCP snooping for the
◆
selected VLAN. When DHCP snooping is enabled globally on the switch,
and enabled on the specified VLAN, DHCP packet filtering will be
performed on any untrusted ports within the VLAN. (Default: Disabled)
W
I
EB
NTERFACE
To configure global settings for DHCP Snooping:
Click Security, DHCP Snooping.
1.
Select Configure VLAN from the Step list.
2.
Enable DHCP Snooping on any existing VLAN.
3.
Click Apply
4.
Figure 207: Configuring DHCP Snooping on a VLAN
Use the IP Service > DHCP > Snooping (Configure Interface) page to
configure switch ports as trusted or untrusted.
CLI R
EFERENCES
◆
"ip dhcp snooping trust" on page 775
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U
OMMAND
SAGE
A trusted interface is an interface that is configured to receive only
◆
messages from within the network. An untrusted interface is an
interface that is configured to receive messages from outside the
network or fire wall.
When DHCP snooping is enabled both globally and on a VLAN, DHCP
◆
packet filtering will be performed on any untrusted ports within the
VLAN.
◆
When an untrusted port is changed to a trusted port, all the dynamic
DHCP snooping bindings associated with this port are removed.
Set all ports connected to DHCP servers within the local network or fire
◆
wall to trusted state. Set all other ports outside the local network or fire
wall to untrusted state.
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DHCP Snooping