From: Reshma Pattan Date: Thu, 3 Aug 2017 13:09:40 +0000 (+0100) Subject: doc: add how-to on packet capture framework X-Git-Tag: spdx-start~2232 X-Git-Url: http://git.droids-corp.org/?a=commitdiff_plain;h=629122b8b842b6bd2278c2caf705ef33d41b1a72;p=dpdk.git doc: add how-to on packet capture framework Add How-To doc to describe the use of the pdump library and the dpdk-pdump tool to capture traffic on DPDK ports. Signed-off-by: Reshma Pattan Acked-by: John McNamara --- diff --git a/doc/guides/howto/img/packet_capture_framework.svg b/doc/guides/howto/img/packet_capture_framework.svg new file mode 100644 index 0000000000..a76baf71fd --- /dev/null +++ b/doc/guides/howto/img/packet_capture_framework.svg @@ -0,0 +1,471 @@ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + image/svg+xml + + + + + + + + + DPDK Primary Application + + dpdk-pdumptool + + PCAP PMD + + dpdk_port0 + + librte_pdump + + capture.pcap + + Traffic Generator + + + + + + + diff --git a/doc/guides/howto/index.rst b/doc/guides/howto/index.rst index a483444d3b..468939b684 100644 --- a/doc/guides/howto/index.rst +++ b/doc/guides/howto/index.rst @@ -42,3 +42,4 @@ HowTo Guides vfd virtio_user_for_container_networking virtio_user_as_exceptional_path + packet_capture_framework diff --git a/doc/guides/howto/packet_capture_framework.rst b/doc/guides/howto/packet_capture_framework.rst new file mode 100644 index 0000000000..4467442eae --- /dev/null +++ b/doc/guides/howto/packet_capture_framework.rst @@ -0,0 +1,140 @@ +.. BSD LICENSE + Copyright(c) 2017 Intel Corporation. All rights reserved. + All rights reserved. + + Redistribution and use in source and binary forms, with or without + modification, are permitted provided that the following conditions + are met: + + * Redistributions of source code must retain the above copyright + notice, this list of conditions and the following disclaimer. + * Redistributions in binary form must reproduce the above copyright + notice, this list of conditions and the following disclaimer in + the documentation and/or other materials provided with the + distribution. + * Neither the name of Intel Corporation nor the names of its + contributors may be used to endorse or promote products derived + from this software without specific prior written permission. + + THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + + + +DPDK pdump Library and pdump Tool +================================= + +This document describes how the Data Plane Development Kit (DPDK) Packet +Capture Framework is used for capturing packets on DPDK ports. It is intended +for users of DPDK who want to know more about the Packet Capture feature and +for those who want to monitor traffic on DPDK-controlled devices. + +The DPDK packet capture framework was introduced in DPDK v16.07. The DPDK +packet capture framework consists of the DPDK pdump library and DPDK pdump +tool. + + +Introduction +------------ + +The :ref:`librte_pdump ` library provides the APIs required to +allow users to initialize the packet capture framework and to enable or +disable packet capture. The library works on a client/server model and its +usage is recommended for debugging purposes. + +The :ref:`dpdk-pdump ` tool is developed based on the +``librte_pdump`` library. It runs as a DPDK secondary process and is capable +of enabling or disabling packet capture on DPDK ports. The ``dpdk-pdump`` tool +provides command-line options with which users can request enabling or +disabling of the packet capture on DPDK ports. + +The application which initializes the packet capture framework will act as a +server and the application that enables or disables the packet capture will +act as a client. The server sends the Rx and Tx packets from the DPDK ports +to the client. + +In DPDK the ``testpmd`` application can be used to initialize the packet +capture framework and act as a server, and the ``dpdk-pdump`` tool acts as a +client. To view Rx or Tx packets of ``testpmd``, the application should be +launched first, and then the ``dpdk-pdump`` tool. Packets from ``testpmd`` +will be sent to the tool, which then sends them on to the Pcap PMD device and +that device writes them to the Pcap file or to an external interface depending +on the command-line option used. + +Some things to note: + +* The ``dpdk-pdump`` tool can only be used in conjunction with a primary + application which has the packet capture framework initialized already. In + dpdk, only ``testpmd`` is modified to initialize packet capture framework, + other applications remain untouched. So, if the ``dpdk-pdump`` tool has to + be used with any application other than the testpmd, the user needs to + explicitly modify that application to call the packet capture framework + initialization code. Refer to the ``app/test-pmd/testpmd.c`` code and look + for ``pdump`` keyword to see how this is done. + +* The ``dpdk-pdump`` tool depends on the libpcap based PMD which is disabled + by default in the build configuration files, owing to an external dependency + on the libpcap development files. Once the libpcap development files are + installed, the libpcap based PMD can be enabled by setting + ``CONFIG_RTE_LIBRTE_PMD_PCAP=y`` and recompiling the DPDK. + + +Test Environment +---------------- + +The overview of using the Packet Capture Framework and the ``dpdk-pdump`` tool +for packet capturing on the DPDK port in +:numref:`figure_packet_capture_framework`. + +.. _figure_packet_capture_framework: + +.. figure:: img/packet_capture_framework.* + + Packet capturing on a DPDK port using the dpdk-pdump tool. + + +Configuration +------------- + +Modify the DPDK primary application to initialize the packet capture framework +as mentioned in the above notes and enable the following config options and +build DPDK:: + + CONFIG_RTE_LIBRTE_PMD_PCAP=y + CONFIG_RTE_LIBRTE_PDUMP=y + + +Running the Application +----------------------- + +The following steps demonstrate how to run the ``dpdk-pdump`` tool to capture +Rx side packets on dpdk_port0 in :numref:`figure_packet_capture_framework` and +inspect them using ``tcpdump``. + +#. Launch testpmd as the primary application:: + + sudo ./app/testpmd -c 0xf0 -n 4 -- -i --port-topology=chained + +#. Launch the pdump tool as follows:: + + sudo ./build/app/dpdk-pdump -- \ + --pdump 'port=0,queue=*,rx-dev=/tmp/capture.pcap' + +#. Send traffic to dpdk_port0 from traffic generator. + Inspect packets captured in the file capture.pcap using a tool + that can interpret Pcap files, for example tcpdump:: + + $tcpdump -nr /tmp/capture.pcap + reading from file /tmp/capture.pcap, link-type EN10MB (Ethernet) + 11:11:36.891404 IP 4.4.4.4.whois++ > 3.3.3.3.whois++: UDP, length 18 + 11:11:36.891442 IP 4.4.4.4.whois++ > 3.3.3.3.whois++: UDP, length 18 + 11:11:36.891445 IP 4.4.4.4.whois++ > 3.3.3.3.whois++: UDP, length 18 diff --git a/doc/guides/tools/pdump.rst b/doc/guides/tools/pdump.rst index b46a92f5b8..16502f7a26 100644 --- a/doc/guides/tools/pdump.rst +++ b/doc/guides/tools/pdump.rst @@ -28,6 +28,7 @@ (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. +.. _pdump_tool: dpdk-pdump Application ======================