BigIron RX Series Configuration Guide
997
53-1001810-01
DHCP relay agent information (DHCP option 82)
35
This
Brocade
device inserts DHCP option 82 when relaying DHCP request packets to DHCP servers,
and deletes option 82 when forwarding server reply packets back to DHCP clients. See the
following figures.
FIGURE 131
DHCP option 82 is added to the packet
FIGURE 132
DHCP Option 82 Is Removed from the Packet
The option 82 insertion/deletion feature is available only when DHCP snooping is enabled for the
client/server ports, and when the device is configured as a DHCP relay agent.
DHCP option 82 contains sub-options such as the following:
•
Supports sub-option 1, the relay agent circuit ID, with the sub-option data in the following
format.
VLAN id (2 bytes) / module id (1 byte) / port id (1 byte)
The circuit ID identifies the location of the port, showing where the DHCP request comes from.
Typical address allocation is based on the gateway address of the relay agent.
Disabling option 82 processing
When DHCP snooping is enabled on the
Brocade
device, option 82 processing is enabled by
default.
To disable option 82 processing, enter the following commands.
BigIron RX(config)# interface ethernet 1/1
BigIron RX(config-if-e10000-1/1)# no dhcp relay information
DHCP
Client
DHCP
Server
T
rusted
Untrusted
DHCP
Snooping
BigIron RX
DHCP Relay Agent
option 82
DHCP client
request packet
+
option 82
DHCP
Client
DHCP
Server
DHCP Server
reply packet
T
rusted
Untrusted
DHCP
Snooping
option 82
BigIron RX
DHCP Relay Agent
option 82
Содержание Brocade DCX
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Страница 88: ...16 BigIron RX Series Configuration Guide 53 1001810 01 Searching and filtering output 1 ...
Страница 300: ...228 BigIron RX Series Configuration Guide 53 1001810 01 Displaying IP information 7 ...
Страница 318: ...246 BigIron RX Series Configuration Guide 53 1001810 01 Deploying a LAG 8 ...
Страница 418: ...346 BigIron RX Series Configuration Guide 53 1001810 01 SuperSpan 12 ...
Страница 482: ...410 BigIron RX Series Configuration Guide 53 1001810 01 MRP CLI example 14 ...
Страница 506: ...434 BigIron RX Series Configuration Guide 53 1001810 01 Displaying VSRP information 15 ...
Страница 566: ...494 BigIron RX Series Configuration Guide 53 1001810 01 QoS for the oversubscribed 16 x 10GE modules 18 ...
Страница 582: ...510 BigIron RX Series Configuration Guide 53 1001810 01 Viewing Layer 2 ACLs 20 ...
Страница 634: ...562 BigIron RX Series Configuration Guide 53 1001810 01 Troubleshooting ACLs 21 ...
Страница 642: ...570 BigIron RX Series Configuration Guide 53 1001810 01 Trunk formation 22 ...
Страница 746: ...674 BigIron RX Series Configuration Guide 53 1001810 01 Displaying RIP filters 24 ...
Страница 808: ...736 BigIron RX Series Configuration Guide 53 1001810 01 Displaying OSPF information 25 ...
Страница 926: ...854 BigIron RX Series Configuration Guide 53 1001810 01 Generalized TTL security mechanism support 26 ...
Страница 938: ...866 BigIron RX Series Configuration Guide 53 1001810 01 Displaying MBGP information 27 ...
Страница 950: ...878 BigIron RX Series Configuration Guide 53 1001810 01 Using secure copy 28 ...
Страница 988: ...916 BigIron RX Series Configuration Guide 53 1001810 01 Clearing IS IS information 29 ...
Страница 998: ...926 BigIron RX Series Configuration Guide 53 1001810 01 Configuring BFD for the specified protocol 30 ...
Страница 1014: ...942 BigIron RX Series Configuration Guide 53 1001810 01 Displaying multi device port authentication information 31 ...
Страница 1054: ...982 BigIron RX Series Configuration Guide 53 1001810 01 Sample 802 1x configurations 33 ...
Страница 1072: ...1000 BigIron RX Series Configuration Guide 53 1001810 01 IP source guard 35 Syntax show ip source guard ethernet port num ...
Страница 1108: ...1036 BigIron RX Series Configuration Guide 53 1001810 01 sFlow 39 ...
Страница 1190: ...1118 BigIron RX Series Configuration Guide 53 1001810 01 Displaying RIPng information 44 ...
Страница 1270: ...1198 BigIron RX Series Configuration Guide 53 1001810 01 Displaying ACLs 47 ...
Страница 1310: ...1238 BigIron RX Series Configuration Guide 53 1001810 01 Displaying OSPFv3 information 48 ...
Страница 1382: ...1310 BigIron RX Series Configuration Guide 53 1001810 01 Commands That Require a Reload D ...
Страница 1435: ...BigIron RX Series Configuration Guide 1363 53 1001810 01 VSRP E ...
Страница 1436: ...1364 BigIron RX Series Configuration Guide 53 1001810 01 VSRP E ...