Licensing Requirements and Limitations for URPF

Involved Network Elements

Other network elements are not required.

Licensing Requirements

Unicast Reverse Path Forwarding (URPF) is a basic feature of a switch and is not under license control.

Feature Support in V200R019C10

Only the following switch models support URPF:

S5720-EI, S5720-HI, S5720I-SI, S5720S-SI, S5720-SI, S5735-S, S5735S-S, S5735-S-I, S5730-HI, S5730S-EI, S5730-SI, S5731-H, S5731-S, S5731S-H, S5731S-S, S5732-H, S6720-EI, S6720-HI, S6720S-EI, S6720S-SI, S6720-SI, S6730-H, S6730S-H, S6730-S, and S6730S-S

For details about software mappings, visit Hardware Query Tool and search for the desired product model.

Feature Limitations

• For the S5735-S, S5735-S-I, and S5735S-S, URPF checks IPv4 and IPv6 packets. For other switch models, URPF checks IPv4 and IPv6 packets but does not check the following packets:
  • BOOTP, DHCP, and DHCPv6 packets
  • Packets with the source port number 67 and destination port number 68
  • Packets with the source port number 68 and destination port number 67
• The S5720I-SI, S5720S-SI, S5720-SI, S5730S-EI, S5730-SI, S6720S-SI, and S6720-SI only support URPF strict check.
• For the S5735-S-I, only URPF check in loose mode is supported. For the S5735-S and S5735S-S, V200R019C10 and later versions support only URPF check in loose mode. If URPF check in strict mode is configured in V200R019C00, the configuration will be changed to URPF check in loose mode after the version is upgraded to V200R019C10 or later.

• For the S5720I-SI, S5720S-SI, S5720-SI, S5730S-EI, S5730-SI, S6720S-SI, and S6720-SI, after a stack is set up, if slot slot-id is not specified when the urpf (system view) command is executed, URPF takes effect only on the master switch.

• For the S5720-EI, S6720-EI, and S6720S-EI, the number of FIB entries are reduced by half if URPF is enabled. You are advised to enable URPF before services are deployed. If you need to enable URPF after services are deployed, configure URPF when less traffic is transmitted and ensure that network requirements are met if the number of FIB entries is reduced by half.