From owner-freebsd-geom@FreeBSD.ORG Fri Jul 11 19:09:05 2008 Return-Path: Delivered-To: freebsd-geom@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 1D43410656BF for ; Fri, 11 Jul 2008 19:09:05 +0000 (UTC) (envelope-from tapan.list@gmail.com) Received: from qb-out-0506.google.com (qb-out-0506.google.com [72.14.204.229]) by mx1.freebsd.org (Postfix) with ESMTP id C65878FC2B for ; Fri, 11 Jul 2008 19:09:04 +0000 (UTC) (envelope-from tapan.list@gmail.com) Received: by qb-out-0506.google.com with SMTP id o21so1323137qba.7 for ; Fri, 11 Jul 2008 12:09:04 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:message-id:date:from:to :subject:in-reply-to:mime-version:content-type:references; bh=VQvVlvHG+8Lj+OndTll/aTHKrOPl8sHXRl3weJ8oqPM=; b=uQbRhjmkOY32edGhhY1dU1wJH+HusYED2z5DOT3l4z1YiJ8DtCn9uKUVq2I5ONFse0 HSqOmb2CuITMIGOYTUVePuJqmzUOKZ9eFHp9xIE64cc1br3DqY4c9R9yFTtSayN6CPfu eR6cWpXHV0Hvs0cQZJLnE3Vr0bpp7cCNgBMXM= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:to:subject:in-reply-to:mime-version :content-type:references; b=TV4/aP1KwLQkVKWPZSteWRf0Ub01+2pePH3cbYZ+q0+qaMDulwkyp3rXReJS5is6zi n3rGDKLpes6uQtOxt4OpJ5aA8U4Mu4LdRhQOUsyWyu107BjqsRZGs2OzodZjpH7DswtP 6Welj8UciAkOuC+hil0WJ3o8XpUvS0YsTIgYY= Received: by 10.103.192.10 with SMTP id u10mr5664612mup.29.1215803343217; Fri, 11 Jul 2008 12:09:03 -0700 (PDT) Received: by 10.103.227.19 with HTTP; Fri, 11 Jul 2008 12:09:03 -0700 (PDT) Message-ID: <482257ad0807111209g20cdb0f6j9f7000fd57a7287a@mail.gmail.com> Date: Sat, 12 Jul 2008 00:39:03 +0530 From: "Tapan Chaudhari" To: freebsd-geom@freebsd.org In-Reply-To: <482257ad0807111129i66ac4372sbc9b4d4ef7675e9d@mail.gmail.com> MIME-Version: 1.0 References: <482257ad0807100541s2d2c3d1eo6cd57c3a1bc338d1@mail.gmail.com> <200807102309.03191.mark@legios.org> <482257ad0807100655u1a5c660awfad05564e40e9a95@mail.gmail.com> <482257ad0807111129i66ac4372sbc9b4d4ef7675e9d@mail.gmail.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Content-Disposition: inline X-Content-Filtered-By: Mailman/MimeDel 2.1.5 Subject: Re: Can GEOM be used to intercept the I/o calls to an existing mounted device? X-BeenThere: freebsd-geom@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: GEOM-specific discussions and implementations List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 11 Jul 2008 19:09:05 -0000 Hi, I got the problem resolved of not getting mails. It was the stupid of me that changed the settings :-).. I have unchecked the digest. Did Ivan sent some attachment with the mail? An attachment was scrubbed in the digest I received. Sorry for the trouble but still, can anyone resend it? Expecting some help regarding "interception mechanism" from all of you. Thanks, --Tapan. On Fri, Jul 11, 2008 at 11:59 PM, Tapan Chaudhari wrote: > Hey guys, > First of all, I was not able to receive your replies to my mail. I > don't know the reason but I am already subscribed to the list. I got to know > about your replies from the digest i received today. I have written a mail > to the mailing list owner describing this problem. Hope this does not happen > again. > > > Well regarding GEOM as Poul mentioned he has already done this interception > mechanism in GEOM, Poul can you please help me out by giving some directions > as to how to move ahead and implement the interceptions of i/o to a > particular device? I would be really happy to get any help regarding the > interception mechanism. > > Thanks, > --Tapan. > > > On Thu, Jul 10, 2008 at 7:25 PM, Tapan Chaudhari > wrote: > >> Thanks Mark, but unmounting will anyways work. But the problem here will >> be, a new device "/dev/mirror/gm0" and "/dev/mirror/gm0s1" will be created >> after :- >> >> #gmirror label -v -n -b round-robin gm0 /dev/md0 >> #gmirror load >> #gmirror configure -a gm0 >> >> and "/dev/md0s1" gets deleted. >> Now I will have to mount the new device "/dev/mirror/gm0s1" to get my >> original contents. >> Can't I do it on the fly while the device is already mounted? I just want >> that all the calls going to the device "/dev/md0s1" first come to me and >> then it goes to the original device. In short intercepting the i/o calls. Is >> there some way I can achieve this? >> >> Thanks, >> >> >> On Thu, Jul 10, 2008 at 6:39 PM, Mark Gladman wrote: >> >>> On Thursday 10 July 2008 22:41:25 Tapan Chaudhari wrote: >>> > Hi All, >>> > I am a newbie to FreeBSD and GEOM. I wanted to intercept the i/o >>> calls >>> > going to a particular mounted device by writing some driver. >>> > I came across geom and thought it might work. I tried to create a new >>> > device, mount it and then tried using gmirror to mirror the device :- >>> > >>> > #dd if=/dev/zero of=file1 bs=1M count=10 >>> > #dd if=/dev/zero of=file2 bs=1M count=10 >>> > #mdconfig -f file1 >>> > #mdconfig -f file2 >>> > #fdisk -B /dev/mirror/md0 >>> > #newfs /dev/mirror/md0s1 >>> > #mkdir /mnt/mirror0 >>> > #mount /dev/mirror/md0s1 /mnt/mirror0/ >>> > >>> > #gmirror label -v -n -b round-robin gm0 /dev/md0 >>> > gmirror: Can't store metadata on /dev/md0: Operation not permitted. >>> > >>> > It gave me this error "gmirror: Can't store metadata on /dev/md0: >>> Operation >>> > not permitted." >>> > >>> > Am I doing something wrong? Or GEOM does not permit me intercept the >>> i/o >>> > calls? If not geom, is there any other mechanism by which I can achieve >>> it? >>> > >>> > >>> > Thanks, >>> > --Tapan. >>> > _______________________________________________ >>> > freebsd-geom@freebsd.org mailing list >>> > http://lists.freebsd.org/mailman/listinfo/freebsd-geom >>> > To unsubscribe, send any mail to "freebsd-geom-unsubscribe@freebsd.org >>> " >>> >>> Hey, >>> >>> You're attempting to set up gmirror on a mounted device. >>> Unmount /dev/mirror/md0s1 then retry the gmirror command and it should >>> work. >>> >>> Cheers! >>> Mark >>> >> >> >