Dell C1048P Port Extender Networking Configuration Guide for the C9000 Series - Page 400
Configuring a Relay Agent, Dynamic Host Configuration Protocol DHCP
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You can configure an interface on the Dell Networking system to relay the DHCP messages to a specific DHCP server using the ip helper-address command from INTERFACE mode, as shown in the following illustration. Specify multiple DHCP servers by using the ip helper-address command multiple times. When you configure the ip helper-address command, the system listens for DHCP broadcast messages on port 67. The system rewrites packets received from the client and forwards them via unicast to the DHCP servers; the system rewrites the destination IP address and writes its own address as the relay device. Responses from the server are unicast back to the relay agent on port 67 and the relay agent rewrites the destination address and forwards the packet to the client subnet via broadcast or unicast, depending whether the client has set or cleared the BROADCAST flag in the DHCP Client PDUs. NOTE: DHCP Relay is not available on Layer 2 interfaces and VLANs. Figure 35. Configuring a Relay Agent Dynamic Host Configuration Protocol (DHCP) 400
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-
1,220
-
1,221
-
1,222
-
1,223
-
1,224
-
1,225
-
1,226
-
1,227
-
1,228
-
1,229
-
1,230
-
1,231
-
1,232
-
1,233
-
1,234
-
1,235
-
1,236
-
1,237
-
1,238
-
1,239
-
1,240
-
1,241
-
1,242
-
1,243
-
1,244
-
1,245
-
1,246
-
1,247
-
1,248
-
1,249
-
1,250
-
1,251