Configuring Source IP Addresses Verification

Procedure

1. Run system-view

   The system view is displayed.

2. Run interface interface-type interface-number

   The interface view is displayed.

3. (Optional) On an Ethernet interface, run undo portswitch

   The interface is switched to Layer 3 mode.

   By default, an Ethernet interface works in Layer 2 mode.

   

   Only the S5720-EI, S5720-HI, S5730-HI, S5731-H, S5731-S, S5731S-H, S5731S-S, S5732-H, S6720-EI, S6720-HI, S6720S-EI, S6730-H, S6730S-H, S6730-S, and S6730S-S support switching between Layer 2 and Layer 3 modes.

4. Run ip verify source-address

   Source IP address verification is configured.

   By default, an interface does not check validity of source IP addresses of received packets.

   The interface only checks validity of source IP addresses of the packets that need to be forwarded to the CPU, and does not check validity of source IP addresses of the packets that will be directly forwarded according to the FIB table.

   If the mask in the IP address of the received packet is of 31 bits, the receiver considers it as a valid source address without checking the broadcast address of the subnet.