From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from dpdk.org (dpdk.org [92.243.14.124]) by inbox.dpdk.org (Postfix) with ESMTP id D4C95A10DA for ; Fri, 2 Aug 2019 09:16:11 +0200 (CEST) Received: from [92.243.14.124] (localhost [127.0.0.1]) by dpdk.org (Postfix) with ESMTP id 93E9F1C235; Fri, 2 Aug 2019 09:16:04 +0200 (CEST) Received: from smtp2.iitb.ac.in (smtp2.iitb.ac.in [103.21.125.13]) by dpdk.org (Postfix) with ESMTP id 0592E1C22A for ; Fri, 2 Aug 2019 09:16:00 +0200 (CEST) Received: from ldns4.iitb.ac.in (ldns4.iitb.ac.in [10.200.12.4]) by smtp2.iitb.ac.in (Postfix) with SMTP id 1AA01104D0B0 for ; Fri, 2 Aug 2019 12:46:00 +0530 (IST) Received: (qmail 31920 invoked by uid 510); 2 Aug 2019 12:46:00 +0530 X-Qmail-Scanner-Diagnostics: from 10.200.25.25 by ldns4 (envelope-from , uid 501) with qmail-scanner-2.11 spamassassin: 3.4.1. mhr: 1.0. {clamdscan: 0.100.0/25528} Clear:RC:1(10.200.25.25):SA:0(0.0/7.0):. Processed in 4.199042 secs; 02 Aug 2019 12:46:00 +0530 X-Spam-Checker-Version: SpamAssassin 3.4.1 (2015-04-28) on ldns4.iitb.ac.in X-Spam-Level: X-Spam-Status: No, score=0.0 required=7.0 tests=HTML_MESSAGE,IITB_ORIG, PROPER_IITB_MSGID autolearn=disabled version=3.4.1 X-Spam-Pyzor: Reported 0 times. X-Envelope-From: nileshunhale@cse.iitb.ac.in X-Qmail-Scanner-Mime-Attachments: | X-Qmail-Scanner-Zip-Files: | Received: from unknown (HELO ldns4.iitb.ac.in) (10.200.25.25) by ldns2.iitb.ac.in with SMTP; 2 Aug 2019 12:45:55 +0530 Received: from smtp-auth.iitb.ac.in (smtpauth1.iitb.ac.in [10.200.8.1]) by ldns4.iitb.ac.in (Postfix) with ESMTP id 78CDB341A71; Fri, 2 Aug 2019 12:45:55 +0530 (IST) Received: from [10.129.131.157] (unknown [10.129.131.157]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: 183050050) by smtp-auth.iitb.ac.in (Postfix) with ESMTPSA id 73D7630C32D; Fri, 2 Aug 2019 12:45:55 +0530 (IST) From: Nilesh To: dev@dpdk.org, users@dpdk.org Message-ID: Date: Fri, 2 Aug 2019 12:45:55 +0530 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.8.0 MIME-Version: 1.0 Content-Language: en-US Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit X-Content-Filtered-By: Mailman/MimeDel 2.1.15 Subject: [dpdk-users] Unable to redirect packets into kernel using dtap/dtun X-BeenThere: users@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: DPDK usage discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: users-bounces@dpdk.org Sender: "users" Hello, We are building an application where a majority of the packets on the fast path are handled by DPDK, but a small subset of packets on the slow path need to be redirected to a legacy userspace socket program that runs over the kernel TCP/IP stack. Therefore, we are trying to inject the slow path packets received by DPDK into the kernel via TUN/TAP device. We have done the following: we created a tun device, assigned it an IP address, and bound the legacy socket program to this address. The DPDK program reads all packets from the NIC and writes the slow path packets into this tun device. These packets are then successfully received by the legacy socket program. However, we are unable to get this to work with DPDK's tun/tap devices (dtun/dtap). When we use dtap then packet is received in dtap0 (can be seen in wireshark) but not reached the socket program. When we use dtun then packet is received in dtun0 (rx value increases but is not captured by wireshark) and not reached the socket program. (We enabled ip_forwarding and disabled rp_filter for both "all" and "dtun0" iface) (Reference:https://doc.dpdk.org/guides/nics/tap.html) Any pointers regarding how to do this using dtun/dtap will be helpful. Are we missing anything due to which linux tun device is working but dtun/dtap isn't? System specification : 2 machines with Distributor ID:    Ubuntu Description:    Ubuntu 18.04.2 LTS Release:    18.04 Codename:    bionic Kernel: 4.15.0-55-generic *DPDK* version: 19.05.0 Hardware: CPU: Intel(R) Xeon(R) CPU E5-2650 v4 @ 2.20GHz NIC 1: Intel Corporation Ethernet Controller XL710 for 40GbE QSFP+ (i40e) (If any extra setup configuration information required will be provided) Regards, Nilesh