From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mails.dpdk.org (mails.dpdk.org [217.70.189.124]) by inbox.dpdk.org (Postfix) with ESMTP id E78E9489EF for ; Mon, 27 Oct 2025 17:08:13 +0100 (CET) Received: from mails.dpdk.org (localhost [127.0.0.1]) by mails.dpdk.org (Postfix) with ESMTP id DC6F8402E1; Mon, 27 Oct 2025 17:08:13 +0100 (CET) Received: from mail-pf1-f171.google.com (mail-pf1-f171.google.com [209.85.210.171]) by mails.dpdk.org (Postfix) with ESMTP id 6ADC44028E for ; Mon, 27 Oct 2025 17:08:13 +0100 (CET) Received: by mail-pf1-f171.google.com with SMTP id d2e1a72fcca58-7a26b04bfc8so5404624b3a.2 for ; Mon, 27 Oct 2025 09:08:13 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=networkplumber-org.20230601.gappssmtp.com; s=20230601; t=1761581292; x=1762186092; darn=dpdk.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:subject:cc:to:from:date:from:to:cc:subject:date :message-id:reply-to; bh=1UNxEJhKfnmuJawTlr0KPBsAV5JSa8QWiCE74rFOdxI=; b=NhkOUR/yKeh4xjhZVF19XLgu3eMeD+GAdlJRXg+aqmZax1EaFG+0XR6WbDvTdQcy7F SwKPKEwbFVLLvQdT8uNew+Pbj750kkZl0emCKPd3iLU/2tVG41mwvHeo7FYTUPy3F/gJ Rk+Y4/dU8qaNBqmCOs/bRxdcY0rCoLJE4B9O1EjqBXK4WIvJIrIZXbXX1ib5Bre7R1Jq dAypRFzevB4iRL+5wDvTNgdglA8yV61RUxP5n4WehocIIECUOx3Pmq0C7ezsKVeN/dPA ltfbAI9PO0EzNU1eUhqqCARsu7SH5UYrg2f0Gtv5exCcQrp8EohxsKuf5VI+tqVt6YOp shdQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1761581292; x=1762186092; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:subject:cc:to:from:date:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=1UNxEJhKfnmuJawTlr0KPBsAV5JSa8QWiCE74rFOdxI=; b=RDcnr75bQs5GVINBNUM8W3uYKELPmKohPYoscZqQW6sofhHXl871SjFqe07QHpF1JX ZSg1EV2A89F0M0lU+8xPV1BvMRf7XWlw4rrjRi4plCtKgb//JEQJbC2EhPLF9AD7KxE5 ldOHdPRz/Pi79Q+JVN9fUpVTCjf170rFSD6xUS1sLAOO99A+W+3jJF5MIIq6x1dgrKeU lNVh9YnxUdBFR10LYjjTBbbOlzJ5cLSxU0pX7gtwRNLmWj6d7RUMctvYb/d15VfJvyrj 1ZlT0pJqTVeiwDI8JpiWUcfpKChenDhPajz9StVGMridGXahhAee+Rvfnt3OFwmW+caG 1oXA== X-Gm-Message-State: AOJu0YxrQE/YS3Mw6RZMTjB2fzyAq8PEUuomiydGISDxNEuGbukHR+uf U2Bu9BlFgN3n+D8Jpk5hwbrdWO/exaWPZEpfahUprxNI71kpprzz7C0CNEF0ThqAqNYrzx+TuN5 +0BuGGUA= X-Gm-Gg: ASbGncv2YKgenSrDY5qXBXTx1CoZgeSI+XPu27HdZ4KgDjuuRttkSdLnORtrAeUxn4L FU1kDmJGGldbw8SrGiVPE+LryqFkBIOghOFMDLs9qCYQkWC27UtUXtHdHEIRntSPClkN6seUi95 FPHsKGKjZx8A6XsW8YpSA0wz03kbXfweUIGoObehi5pqhskgKZcMzC9TtKFupZNA1syuMviGkNn QvesNMsP+SVq/ZVxxoZzwhAZsdfeMeJmMaLIFZd+Fu9RKEHb7YnQOgnkGMYgTbJB7Ldjj525WLt EmETvKWEuizlFzlnuC0ls3uhryDzKPkktlAzNaZJx5UqYateOCdLCijoKxzUHk3Zz44Bh5E6+RG mA5kH0BgfSN50ap0NfrHZaz5p19qacGVA5UWDyqp/g+AziNXmX2+FQIdR/DBDLHpX/XbsjT/M5E dKxGqDsDuxmZB/m0mLvvt/+zDMVUBFuFtuKiD9kApl/Mbg X-Google-Smtp-Source: AGHT+IGhrQ2jLpLxEn/YN4T+72OsU7MqvJrBb6Rx5jEY6DQ7iouGUIcm80+ETmEMpJn2aqZ0Lps6wg== X-Received: by 2002:a05:6a20:9143:b0:342:e2ee:bac7 with SMTP id adf61e73a8af0-344d19b93c5mr245089637.12.1761581292389; Mon, 27 Oct 2025 09:08:12 -0700 (PDT) Received: from phoenix (204-195-96-226.wavecable.com. [204.195.96.226]) by smtp.gmail.com with ESMTPSA id d2e1a72fcca58-7a4140978dfsm8565407b3a.69.2025.10.27.09.08.11 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 27 Oct 2025 09:08:12 -0700 (PDT) Date: Mon, 27 Oct 2025 09:08:09 -0700 From: Stephen Hemminger To: "Nicolson Ken (=?UTF-8?B?44OL44Kz44Or44K944OzIOOCseODsw==?=)" Cc: "users@dpdk.org" Subject: Re: Tapping a Tx port to access all the packets being Txed Message-ID: <20251027090809.1972efd9@phoenix> In-Reply-To: References: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable X-BeenThere: users@dpdk.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: DPDK usage discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: users-bounces@dpdk.org On Thu, 11 Jan 2024 05:55:53 +0000 Nicolson Ken (=E3=83=8B=E3=82=B3=E3=83=AB=E3=82=BD=E3=83=B3 =E3=82=B1=E3=83= =B3) wrote: > Hi all, >=20 > I'm wanting to basically tap a DPDK stream and for instance save all pack= ets being Txed by a PMD to a separate file. >=20 > I know I could relatively easily modify an existing PMD to have two outpu= t ports, but is there either an existing PMD that does this, or a programma= tic way to graft a second port onto an arbitrary PMD, or is there another s= impler way that I haven't realised yet. As mbufs are already reference coun= ted, I would hope, and require, that such a solution would be zero copy. RS= S-friendly would also be a plus. >=20 > Thanks, > Ken I started doing this with mirror support but decided it was adding more com= plexity. The main use of taps was for debugging and pdump/dumpcap handle that.