From owner-freebsd-net@freebsd.org Wed Sep 13 16:11:35 2017 Return-Path: Delivered-To: freebsd-net@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id C18F9E03660 for ; Wed, 13 Sep 2017 16:11:35 +0000 (UTC) (envelope-from matt.joras@gmail.com) Received: from mail-wm0-f45.google.com (mail-wm0-f45.google.com [74.125.82.45]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G2" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 5D8536BD1D for ; Wed, 13 Sep 2017 16:11:35 +0000 (UTC) (envelope-from matt.joras@gmail.com) Received: by mail-wm0-f45.google.com with SMTP id a137so9385484wma.0 for ; Wed, 13 Sep 2017 09:11:35 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:in-reply-to:references:from:date :message-id:subject:to:cc; bh=yeSMkEWwyW9UMI/R1Boet5DgIWwH+ue7vytyNkv5RFk=; b=ZSTOjmzTO+j0q7Vmv0eP8huJPT1d2/aYb+4Seoou18ZNCqpO+C102B7hKUDJPHRT4+ wbgYfqfNHmYwabLfTcwK48NLkq/hO7z/OXCPdfxrFJMS+7JvLpW6tZBpTk4gB0zbpRjv 26JM2ufFZgyNIXXjBdvBragz2t/E3o8PXyG9q9EjY+mGED9dTgiM+nckvcKaSYoodTOA arjJUf/79ijGrWgP8jZwqVAaA8jf4A5fddZ4733W8dwx04lpbsbSmnTw5dFQtLUJJA7o sbB/DUDm4O91Df6GF+g72CEnoT8LWEgk8e5pG4d9boHRBt+57aos2c2+fyJEi0riRICb JeKw== X-Gm-Message-State: AHPjjUjbxjN1QpHf8RT9sRg0GVr9t8aJXxvZSvSDGB4V1/zWbnAvCyy/ I7YzKtlZKJXfwJSZlcThCQ== X-Received: by 10.80.141.133 with SMTP id r5mr9850364edh.107.1505313014937; Wed, 13 Sep 2017 07:30:14 -0700 (PDT) Received: from mail-wm0-f48.google.com (mail-wm0-f48.google.com. [74.125.82.48]) by smtp.gmail.com with ESMTPSA id b43sm8805371edc.52.2017.09.13.07.30.13 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 13 Sep 2017 07:30:14 -0700 (PDT) Received: by mail-wm0-f48.google.com with SMTP id i189so8335427wmf.1 for ; Wed, 13 Sep 2017 07:30:13 -0700 (PDT) X-Google-Smtp-Source: AOwi7QBsV5J90S60J/beHSE+47L8BqQn+ejDwKlKyv8H8pv8p8HD5FjgYRmGgt9zpe0WNxU5tCIxOMcEBNEi+12tOrE= X-Received: by 10.28.142.147 with SMTP id q141mr2508806wmd.155.1505313013353; Wed, 13 Sep 2017 07:30:13 -0700 (PDT) MIME-Version: 1.0 Received: by 10.223.144.106 with HTTP; Wed, 13 Sep 2017 07:30:12 -0700 (PDT) In-Reply-To: References: From: Matt Joras Date: Wed, 13 Sep 2017 07:30:12 -0700 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: Splitting Mellanox ConnectX-4 interface using breakout cables To: David Horn Cc: FreeBSD Net , "Andrey V. Elsukov" Content-Type: text/plain; charset="UTF-8" X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 13 Sep 2017 16:11:35 -0000 On Sep 13, 2017 6:43 AM, "David Horn" wrote: I was under the impression that these Mellanox 40G->4x10G breakout cables were for the Mellanox switch side (not Mellanox NIC) to provide more flexible utilization options for the switch. I have never heard of doing this from the 40G NIC (on any OS). Please reply if you have seen this working on *any* OS from the Mellanox 40G NIC, as I am curious as well and have a both ConnectX-3 and -4 HW. -Dave On Wed, Sep 13, 2017 at 7:00 AM, Andrey V. Elsukov wrote: > Hi All, > > we are wondering, is it possible to use such configuration under > FreeBSD? I.e. split one mce interface 40G => 4x10G or 100G => 4x25G? > > -- > WBR, Andrey V. Elsukov > > I was also under the impression that they were exclusively used on the switch for Mellanox. Mellanox's documentation seems to back this up: "Important: The 40GbE split options is supported only on Mellanox switches and not supported on Mellanox adapters (e.g. ConnectX-3) when equipped with 40GbE ports. In case you wish to limit the 40GbE port on the adapter to 10GbE you can use QSA or similar 40GbE-10GbE cables (Refer to Mellanox.com - here)" [1] That doesn't mention their newer NICs, however, though I don't see a mention of the feature on their product sheets. Matt [1] https://community.mellanox.com/docs/DOC-1450