
C
HAPTER
7
| Security Measures
DHCP Snooping
– 237 –
When DHCP snooping is globally enabled, and DHCP snooping is then
disabled on a VLAN, all dynamic bindings learned for this VLAN are
removed from the binding table.
P
ARAMETERS
These parameters are displayed:
VLAN
– ID of a configured VLAN. (Range: 1-4094)
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
EB
I
NTERFACE
To configure global settings for DHCP Snooping:
1.
Click DHCP Snooping, VLAN Configuration.
2.
Enable DHCP Snooping on any existing VLAN.
3.
Click Apply
Figure 102: Configuring DHCP Snooping on a VLAN
DHCP S
NOOPING
I
NFORMATION
O
PTION
C
ONFIGURATION
Use the DHCP Snooping > Information Option Configuration page to
configure DHCP Snooping Option 82.
CLI R
EFERENCES
"ip dhcp snooping information option" on page 627
"ip dhcp snooping information policy" on page 628
C
OMMAND
U
SAGE
DHCP provides a relay mechanism for sending information about the
switch and its DHCP clients to the DHCP server. Known as DHCP Option
82, it allows compatible DHCP servers to use the information when
assigning IP addresses, or to set other services or policies for clients. It
is also an effective tool in preventing malicious network attacks from
attached clients on DHCP services, such as IP Spoofing, Client Identifier
Spoofing, MAC Address Spoofing, and Address Exhaustion.
When the DHCP Snooping Information Option 82 is enabled, the
requesting client (or an intermediate relay agent that has used the
Summary of Contents for DG-FS4528P
Page 2: ......
Page 4: ......
Page 148: ...CHAPTER 5 Simple Network Management Protocol Configuring SNMPv3 Groups 148 ...
Page 389: ...CHAPTER 17 VoIP Traffic Configuration Configuring Telephony OUI 389 ...
Page 515: ...CHAPTER 22 System Management Commands UPnP 515 TTL 20 Console ...
Page 972: ......
Page 973: ...DG FS4528P ...