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Network application
Figure 137 Network diagram
ISP A
URPF(loose)
URPF(strict)
ISP C
ISP B
Configure strict URPF between each ISP and its connected users, and loose URPF between ISPs.
Configuring URPF
Follow these steps to configure URPF globally:
To do... Use the command… Remarks
Enter system view system-view ––
Enable URPF check globally ip urpf { loose | strict }
Required
Disabled by default.
NOTE:
• The routing table size decreases by half when URPF is enabled on the 3600 v2 switches.
• To prevent loss of routes and packets, URPF cannot be enabled if the number of route entries the switch
maintains exceeds half the routing table size.
URPF configuration example
Network requirements
As shown in Figure 138, a client (Switch A) directly connects to the ISP switch (Switch B). Enable URPF
check on Switch A and Switch B to prevent source address spoofing attacks.