Hi Ori Thank you for your answer it helped me But I can see the load balancing is not done to the same instance for both directions I would like to have ip + port pairs arrive to same instance Now ip1+port1 -> ip2+port2 arrive to instance x and ip2+port2 -> ip1+port1 arrive to another instance How can I solve this? From: Ori Kam Sent: Wednesday, February 14, 2024 6:07 PM To: Yaron Illouz ; dev@dpdk.org; 'users@dpdk.org' Subject: RE: rss calculation as the nic EXTERNAL EMAIL: Do not click links or attachments unless you recognize the sender and know the content is safe Hi Yaron, I can see some possible issues with your code, please see below. From: Yaron Illouz > Sent: Saturday, February 3, 2024 7:03 PM To: dev@dpdk.org; 'users@dpdk.org' > Subject: rss calculation as the nic [Snip] static inline uint32_t do_softrss(struct rte_mbuf *m) { uint32_t input_len; struct rte_ipv4_tuple ipv4_tuple; char * pRawPacket = static_cast(rte_pktmbuf_mtod(pi_mbuf, void* )); IpHeader * pIpHeader = (IpHeader *)(pRawPacket + offsetOfIp); if(pIpHeader->GetVersion()==4) { ipv4_tuple.src_addr = rte_be_to_cpu_32(pIpHeader->dwSrcAddressBigEndian); ipv4_tuple.dst_addr = rte_be_to_cpu_32(pIpHeader->dwDstAddressBigEndian); [Ori] here you are converting BE to CPU ipv4_tuple.sport = *(uint16_t*)(pRawPacket + transportLayerOffset); ipv4_tuple.dport = *(uint16_t*)(pRawPacket + transportLayerOffset+2); [Ori] here you keep the values as BE input_len = RTE_THASH_V4_L3_LEN; return rte_softrss_be((uint32_t *)&ipv4_tuple, input_len, rss_key_be); [Ori] the above function expects to get everything in BE and you should also call rte_convert_rss_key before the use of the above function. } return 0; } new_rss = do_softrss(mbuf_pointer); std::cout<< std::hex << mbuf_pointer->hash.rss << " -> " << new_rss << std::dec << std::endl; And i get a different value than the mbuf_pointer->hash.rss 5ed28a5c -> 33eb33eb 974c1896 -> 24e224e2 1edf1638 -> 21752175 8a54c19 -> 80638063 459a6f76 -> 1b351b35 1cdf1d1c -> e53be53b **** I understand it is possible to do it, but i don't get the same value *** ethtool -i ens5f0 driver: mlx5_core version: 5.8-3.0.7 firmware-version: 22.32.2004 (MT_0000000437) expansion-rom-version: bus-info: 0000:83:00.0 supports-statistics: yes supports-test: yes supports-eeprom-access: no supports-register-dump: no supports-priv-flags: yes