618
C
HAPTER
58: DHCP R
ELAY
A
GENT
C
ONFIGURATION
Specifying address checking fields
After enabled with the address checking function, Switch 7750 Ethernet switches
default to check the IP address, MAC address, VLAN ID, and port number of a
DHCP client respectively. The DHCP client can access external networks only after
an entry matching all the four fields is found in the client address table.
You can disable some fields (MAC address, VLAN ID, or port number) from address
checking as needed. Thus, after enabled with address checking, the DHCP relay
agent will not check the disabled fields, so that the clients not matching all the
fields can also access external networks.
n
If you configure a static client address entry on the DHCP relay agent using the
dhcp-security static
command without specifying the
vlan
or
port
keyword, the
DHCP relay agent will not check the VLAN ID or port number when performing
address checking for the client, even if the two fields are enabled for address
checking.
Configuring dynamic entries
Through this configuration task, you can validate or invalidate the dynamic
IP-to-MAC mapping entries generated by the DHCP relay agent. DHCP client
addresses are matched based on the dynamic entries generated by DHCP relay
agent only after these entries are activated; otherwise, DHCP client addresses are
matched based only on the security address entries statically configured.
Table 490
Specify address checking fields
Operation Command
Description
Enter system view
system-view
-
Enter interface view
interface
interface-type
interface-number
-
Specify address checking
field(s)
address-check field
{
mac | vlan |
port
}
enable
Optional
By default, after
enabled with the
address checking
function, the DHCP
relay agent checks the
IP address, MAC
address, VLAN ID, and
port number of a
DHCP client
respectively.
Disable specified address
checking field(s)
address-check field
{
mac | vlan |
port
}
disable
Table 491
Configure dynamic entries generated by DHCP relay agents
Operation Command
Description
Enter system view
system-view
-
Enter VLAN interface
view
interface
interface-type
interface-number
-
Validate the dynamic
entries generated by
the DHCP relay agent
address-check dhcp-relay
enable
Optional
By default, the dynamic IP-to-MAC
mapping entries generated by the
DHCP relay agent are valid
Summary of Contents for Switch 7754
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 ...