ip ipsec-load-sharing spi

This command enables hashing on the Security Parameters Index (SPI) field in IPsec packets. IPsec packets are IPv4 and IPv6 packets with the following IP protocols:

• IP protocol 50 – Encapsulating Security Payload (ESP)
• IP protocol 51 – Authentication Header (AH).

The ESP and AH protocols do not employ the IP source and destination port numbers, so the hardware does not use the IP port numbers for hashing the packets. The ESP and AH packet headers contain the SPI field, which is associated with packet flows and can be used for hashing IPsec packets.