D-Link DGS-1520 Emulator - Page 203
ip dhcp relay information check
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DGS-1520 Series Gigabit Ethernet Smart Managed Switch CLI Reference Guide Command Default Level Level: 12. Usage Guideline In addition to DHCP relay packets, based on the ip helper-address command, the relay destination of the DHCP server can be specified in the DHCP relay pool. To do this, use the ip dhcp pool command to enter the DHCP pool configuration, use the relay source command to specify the source subnet of the client requests, and use the relay destination command to specify the relay destination server address. When receiving a DHCP request packet, if the subnet that the packet comes from matches the relay source of a relay pool, the packet will be relayed based on the matched relay pool. Otherwise, the packet is relayed based on the IP helper-address configured on the received interface. To relay based on the relay pool, if the request packet is a relayed packet, the Gateway IP Address (GIADDR) of the packet is the source of the request. If the GIADDR is zero, the subnet of the received interface is the source of the packet. Example This example shows how to create a DHCP relay pool, called pool1. In the relay pool, the subnet 172.19.18.0/255.255.255.0 is specified as the source subnet. 10.2.1.1 is specified as the relay destination address. Switch#configure terminal Switch(config)#ip dhcp pool pool1 Switch(config-dhcp-pool)#relay source 172.19.18.0 255.255.255.0 Switch(config-dhcp-pool)#relay destination 10.2.1.1 Switch(config-dhcp-pool)# 20-4 ip dhcp relay information check This command is used to enable the DHCP relay agent to validate and remove the relay agent information option in the received DHCP reply packet. Use the no form of this command to globally disable the check for Option 82. ip dhcp relay information check no ip dhcp relay information check Parameters None. Default By default, this option is disabled. Command Mode Global Configuration Mode. Command Default Level Level: 12. Usage Guideline This command takes effect when the service dhcp command is enabled. The ip dhcp relay information check command and the ip dhcp relay information check-reply command together determine whether the check function of Option 82 is effective for an interface. If the ip dhcp relay information check-reply command is not configured for an interface, the global setting takes effect. If the ip dhcp relay information check-reply command is configured for an interface, the interface setting takes effect. 199
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1,182
-
1,183
-
1,184
-
1,185
-
1,186
-
1,187
-
1,188
-
1,189
-
1,190
-
1,191
-
1,192
-
1,193
-
1,194
-
1,195
-
1,196
-
1,197
-
1,198
-
1,199
-
1,200
-
1,201
-
1,202
-
1,203
-
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