D-Link DGS-1520 Emulator - Page 1178
Unicast Reverse Path Forwarding URPF, Commands
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DGS-1520 Series Gigabit Ethernet Smart Managed Switch CLI Reference Guide 111. Unicast Reverse Path Forwarding (URPF) Commands 111-1 ip urpf This command is used to enable URPF checking globally. Use the no form of this command to disable the global state of URPF. ip urpf no ip urpf Parameters None. Default By default, this option is disabled. Command Mode Global Configuration Mode. Command Default Level Level: 12. Usage Guideline One common method to initiate an attack is to utilize IPv4/IPv6 source address spoofing. When using this method, a hacker attempts to send traffic into the network with a source address that is known or trusted by the target. If no protection exists, the organizational network will allow the traffic and potentially be open to a number of different attack types. URPF helps to mitigate problems caused by malformed or forged IPv4/IPv6 source addresses passing through a router. The ip urpf command is used to enable URPF globally and the ip verify unicast source command is used to enable URPF on the interface. To enable URPF on an interface, enable the function both globally and on the interface. When enabled, the hardware routing table needs to be searched using the Session Initiation Protocol (SIP) first and then using the Dynamic Inspection Protocol (DIP). This is achieved by splitting the table into two halves so that the size of the IP routing table will be reduced by half. This will not take effect until the configuration was saved and the Switch was rebooted. Example This example shows how to enable the URPF checking globally. Switch#configure terminal Switch(config)#ip urpf WARNING: The command does not take effect until after the next reboot. Switch(config)# 111-2 ip verify unicast source This command is used to configure URPF on interfaces. Use the no form of this command to disable URPF checking on an interface or to revert to the default settings 1174
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1,197
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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