[dpdk-dev] hw checksum offload feature issue

[Balasubramanian, RajaramanX]

Hi,

    We are developing CGNAT VNF over DPDK. In that, we have NAT64 feature included which basically does IPv6 to IPv4 NAT translation and vice versa.

    When we do conversion from IPv6 to IPv4, we have used dpdk mbuf library function  rte_pktmbuf_adj() to remove 20 bytes of IPv6 header at the beginning and create IPv4 header and other headers appropriately.

  Also, we have hw checksum offload feature enabled. So when the packet goes through NIC hw checksum, apart from calculating IPv4 and UDP/TCP checksum, it also modifies other header fields like eth header dest address field.

   SO, have you come across any issue like this ??

  When we disable hw checksum feature, packet header fields are not modified and there is no issue.

Thanks,
Rajaram.