D-Link DGS-1520 Emulator - Page 219
ip dhcp smart-relay, option hex DHCP Relay
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DGS-1520 Series Gigabit Ethernet Smart Managed Switch CLI Reference Guide 20-17 ip dhcp smart-relay This command is used to enable smart relay of the DHCP relay agent. Use the no form of this command to disable the function. ip dhcp smart-relay no ip dhcp smart-relay Parameters None. Default By default, this function is disabled. Command Mode Global Configuration Mode. Command Default Level Level: 12. Usage Guideline When the received interface of the packet has secondary addresses, by default, the relay agent set the gateway address field of the packet to the primary address of the interface. When smart relay is enabled, the relay agent will count the number that a client retries sending of the DISCOVER message. The relay agent will change the gateway address to the secondary address of the received interface after three retries. Example This example shows how to enable smart relay. Switch#configure terminal Switch(config)#ip dhcp smart-relay Switch(config)# 20-18 option hex (DHCP Relay) This command is used to specify a DHCP option matching pattern for a DHCP class. Use the no form of this command to delete the specified matching pattern for a DHCP class. option CODE hex PATTERN [*] [bitmask MASK] no option CODE hex PATTERN [*] [bitmask MASK] Parameters CODE PATTERN * Specifies the DHCP option number. Specifies the hexadecimal pattern of the specified DHCP option. The length of the pattern must be even-numbered. Specifies the remaining bits of the option that will not be matched. If * is not specified, the bit length of the pattern should be the same as the bit length of the option. 215
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1,204
-
1,205
-
1,206
-
1,207
-
1,208
-
1,209
-
1,210
-
1,211
-
1,212
-
1,213
-
1,214
-
1,215
-
1,216
-
1,217
-
1,218
-
1,219
-
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
-
1,252
-
1,253
-
1,254
-
1,255
-
1,256
-
1,257
-
1,258
-
1,259
-
1,260
-
1,261
-
1,262
-
1,263
-
1,264
-
1,265
-
1,266
-
1,267
-
1,268
-
1,269
-
1,270
-
1,271
-
1,272
-
1,273
-
1,274
-
1,275
-
1,276
-
1,277
-
1,278
-
1,279
-
1,280
-
1,281
-
1,282
-
1,283
-
1,284
-
1,285
-
1,286
-
1,287
-
1,288
-
1,289
-
1,290
-
1,291
-
1,292
-
1,293
-
1,294
-
1,295
-
1,296
-
1,297
-
1,298
-
1,299
-
1,300
-
1,301
-
1,302
-
1,303
-
1,304
-
1,305
-
1,306
-
1,307
-
1,308
-
1,309
-
1,310
-
1,311