Hi All, Good morning~ I use WindRiver pktgen v2.1.3 on my servers, two server have same hardware. Each one has two Intel Xeon E5-2648L CPU, 32G DDR3 RAM ,two 10G NIC which is supplied by Intel 82599 chip. And the servers are running CentOS6.1 I run pktgen on both side. one as sender, the other as receiver. If I only start transmit on one port, both Tx and Rx looks good, but if I enable two ports, the receiver will get rx error. Please refer the attachment(pktgen_tx.png and pktgen_rx.png). Did anyone meet this issue before? Thank you! PS: Sorry for my bad English, I’m not native. Best Regards Jia Sui