From owner-freebsd-questions@freebsd.org Sun Oct 16 00:22:33 2016 Return-Path: Delivered-To: freebsd-questions@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 42366C065BA for ; Sun, 16 Oct 2016 00:22:33 +0000 (UTC) (envelope-from jd1008@gmail.com) Received: from mail-it0-x235.google.com (mail-it0-x235.google.com [IPv6:2607:f8b0:4001:c0b::235]) (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 09D1E7E6 for ; Sun, 16 Oct 2016 00:22:33 +0000 (UTC) (envelope-from jd1008@gmail.com) Received: by mail-it0-x235.google.com with SMTP id o19so21913145ito.1 for ; Sat, 15 Oct 2016 17:22:33 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=subject:to:references:from:message-id:date:user-agent:mime-version :in-reply-to:content-transfer-encoding; bh=DfIuG3xJt/vd2edVG9ZmHQxiCvNLt3uW3lrHNiDmX0E=; b=f+ywLvrzAWT+gD50S0TOOx4tlDYQWLtX2Ceq1aGQR4NzbO0/MFFIlieWAEY/LbHCme KdbX+1Nl8Sc2fFO7x6QeMYzF160lFzoojlOEpxbhyRU2+TfBBRRx41sB4wUxrLcmaF9w eCeTjDs/LK42SD6J2vHAQtTNK6Ol4zhecOH3bfnVRU1Lx/urAG8ZU3ZaheuJEs1cxcvH K/MboYHyQlpjMB55+gG+6PcmDbo76MP2u0Ov/QUiK6i8BzrYHv9E+X2Wa3SI2uyJsfIe Mfq0B8ox7D2Lz+byv6eHRfKw293af0twvNf4F61/8e3yPxFWlchwzgBr7oS4TwI8qKfm EMxQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:subject:to:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-transfer-encoding; bh=DfIuG3xJt/vd2edVG9ZmHQxiCvNLt3uW3lrHNiDmX0E=; b=CUp2MAOuTVaHAne4USERuAh9+k6NCDos19GaE0L+fVwzsUmRDBjs/6k9rTq2fmeyf3 CTmk9Jm8nsF+Gs0dyHSEcMk2+3Y2BlWjnMTArecGlOed1zot/ASlm1THMf831APhXbKl q5yifzxtCEulav1UKJHllr/v9Y19QCktu1pz06R3wsNG5j6kK3n7hUDlTuJIeY5cRa+z LYSls4LdFZm925qOboAgKUarfRhfcJrEgac6r7O2Kxbrt1SS8r47Mp/g22gQf2gIScUG JJSzsMfjp09yLq31AWhFymcM6GBiko4EtM8wqeohYGS68R9UDmQh9RCFnI2kzKRYK0fh JpEA== X-Gm-Message-State: AA6/9Rl1q987nY4R2wut3QvHEok4Ey4uihO/OWaf0G8E1mUpKwlr+Wx3EShrTFebtOnenw== X-Received: by 10.36.189.195 with SMTP id x186mr3402332ite.80.1476577352364; Sat, 15 Oct 2016 17:22:32 -0700 (PDT) Received: from localhost.localdomain (50-243-4-3-static.hfc.comcastbusiness.net. [50.243.4.3]) by smtp.googlemail.com with ESMTPSA id u6sm2286500itb.3.2016.10.15.17.22.31 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Sat, 15 Oct 2016 17:22:31 -0700 (PDT) Subject: Re: Filesystem Label Ambiguity To: freebsd-questions@freebsd.org References: <86pon1dwze.fsf@WorkBox.Home> From: jd1008 Message-ID: <5802C836.1060607@gmail.com> Date: Sat, 15 Oct 2016 18:22:14 -0600 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.0.1 MIME-Version: 1.0 In-Reply-To: <86pon1dwze.fsf@WorkBox.Home> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 16 Oct 2016 00:22:33 -0000 On 10/15/2016 05:16 PM, Brandon J. Wandersee wrote: > Jason C. Wells writes: > >> Let's say I have three disks and each of them has a partition labelled >> "volume3" i.e. /dev/ufs/volume3. >> >> How can I determine which of those is currently mounted? >> >> How does the system determine which of those to mount at boot time? > Short answer: Don't do this. > > Long answer: The only thing I can think of is to check > /dev/diskid/*. The one filesystem that *does not* have a node > /dev/diskid/* will be the one that's mounted. Of course you'd then have > to figure out what the ID number of each disk/partition is, which is > exactly what unique partition/filesystem labels were invented to avoid. > > If this more than hypothetical, and you have filesystems that already > have labels, they can be changed by running `tunefs -L