632
C
HAPTER
59: DHCP S
NOOPING
C
ONFIGURATION
n
■
Enable DHCP snooping and specify trusted ports on the switch before
configuring IP filtering.
■
You are not recommended to configure IP filtering on the ports of an
aggregation group.
Displaying and
Maintaining DHCP
Snooping
After the above configuration, execute the
display
command in any view to
display and verify the DHCP snooping configuration.
Execute the
reset
command in user view to clear the IP-MAC mappings recorded
by the DHCP-Snooping-enabled switch.
DHCP Snooping
Configuration
Example
DHCP Snooping Trusted
Port Configuration
Example
Network requirements
As shown in Figure 163, the Ethernet 2/0/1 port of Switch A is connected to
Switch B (acting as a DHCP relay agent). A network segment containing some
DHCP clients is connect to the Ethernet 2/0/2 port of Switch A.
■
The DHCP snooping function is enabled on Switch A.
■
The DHCP-Snooping-enabled device supports option 82 and option 82 is
enabled on the switch.
■
The Ethernet 2/0/1 port of Switch A is a trusted port.
Create a static binding
ip source static binding
ip-address
ip-address
[
mac-address
mac-address
]
Optional
By default, no static binding
entry is created.
Table 505
Configure IP filtering
Operation Command Description
Table 506
Display and maintain DHCP snooping configuration
Operation Command
Description
Display the IP-MAC mappings
recorded by the
DHCP-Snooping-enabled switch
display dhcp-snooping
You
can
execute the
display
command in
any view.
Display DHCP-Snooping status and
trusted port information
display dhcp-snooping trust
Display the total number of
DHCP-Snooping binding table entries
display dhcp-snooping count
Display the DHCP-Snooping binding
table entries of the specified VLAN
display dhcp-snooping
vlan
{
vlan-list |
all
}
Display IP static binding table entries
display ip source static binding
[
vlan
vlan-id
|
interface
interface-type interface-number
]
Clear the IP-MAC mappings recorded
by the DHCP-Snooping-enabled
switch
reset dhcp-snooping
[
ip-address
] You
can
execute the
reset
command
in user view.
Summary of Contents for Switch 7757
Page 32: ...32 CHAPTER 1 CLI OVERVIEW...
Page 70: ...70 CHAPTER 5 LOGGING IN USING MODEM...
Page 76: ...76 CHAPTER 7 LOGGING IN THROUGH NMS...
Page 86: ...86 CHAPTER 9 CONFIGURATION FILE MANAGEMENT...
Page 120: ...120 CHAPTER 13 ISOLATE USER VLAN CONFIGURATION...
Page 126: ...126 CHAPTER 14 SUPER VLAN...
Page 136: ...136 CHAPTER 16 IP PERFORMANCE CONFIGURATION...
Page 152: ...152 CHAPTER 17 IPX CONFIGURATION...
Page 164: ...164 CHAPTER 19 QINQ CONFIGURATION...
Page 172: ...172 CHAPTER 21 SHARED VLAN CONFIGURATION...
Page 182: ...182 CHAPTER 22 PORT BASIC CONFIGURATION...
Page 198: ...198 CHAPTER 24 PORT ISOLATION CONFIGURATION...
Page 208: ...208 CHAPTER 25 PORT SECURITY CONFIGURATION...
Page 224: ...224 CHAPTER 27 DLDP CONFIGURATION...
Page 232: ...232 CHAPTER 28 MAC ADDRESS TABLE MANAGEMENT...
Page 240: ...240 CHAPTER 29 CENTRALIZED MAC ADDRESS AUTHENTICATION CONFIGURATION...
Page 280: ...280 CHAPTER 30 MSTP CONFIGURATION...
Page 348: ...348 CHAPTER 35 IS IS CONFIGURATION...
Page 408: ...408 CHAPTER 39 802 1X CONFIGURATION...
Page 412: ...412 CHAPTER 40 HABP CONFIGURATION...
Page 422: ...422 CHAPTER 41 MULTICAST OVERVIEW...
Page 426: ...426 CHAPTER 42 GMRP CONFIGURATION...
Page 480: ...480 CHAPTER 47 PIM CONFIGURATION...
Page 506: ...506 CHAPTER 48 MSDP CONFIGURATION...
Page 552: ...552 CHAPTER 51 TRAFFIC ACCOUNTING CONFIGURATION...
Page 570: ...570 CHAPTER 53 HA CONFIGURATION...
Page 582: ...582 CHAPTER 54 ARP CONFIGURATION SwitchA arp protective down recover interval 200...
Page 622: ...622 CHAPTER 58 DHCP RELAY AGENT CONFIGURATION...
Page 684: ...684 CHAPTER 61 QOS CONFIGURATION...
Page 718: ...718 CHAPTER 63 CLUSTER...
Page 738: ...738 CHAPTER 67 UDP HELPER CONFIGURATION...
Page 752: ...752 CHAPTER 69 RMON CONFIGURATION...
Page 772: ...772 CHAPTER 70 NTP CONFIGURATION...
Page 796: ...796 CHAPTER 72 FILE SYSTEM MANAGEMENT...
Page 802: ...802 CHAPTER 73 BIMS CONFIGURATION...
Page 814: ...814 CHAPTER 74 FTP AND TFTP CONFIGURATION...
Page 830: ...830 CHAPTER 75 INFORMATION CENTER...
Page 836: ...836 CHAPTER 76 DNS CONFIGURATION...
Page 852: ...852 CHAPTER 77 BOOTROM AND HOST SOFTWARE LOADING...
Page 858: ...858 CHAPTER 78 BASIC SYSTEM CONFIGURATION DEBUGGING...