From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from [10.33.1.214] (dhcp-1-214.fab.redhat.com [10.33.1.214]) by pobox.fab.redhat.com (8.13.1/8.13.1) with ESMTP id l4LESZRt008058 for ; Mon, 21 May 2007 10:28:36 -0400 Message-ID: <4651AC93.8090309@redhat.com> Date: Mon, 21 May 2007 15:28:35 +0100 From: "Bryn M. Reeves" MIME-Version: 1.0 Subject: Re: [linux-lvm] Disk /dev/dm-0 doesn't contain a valid partition table References: <247618.80102.qm@web38214.mail.mud.yahoo.com> In-Reply-To: <247618.80102.qm@web38214.mail.mud.yahoo.com> Content-Transfer-Encoding: 7bit Reply-To: LVM general discussion and development List-Id: LVM general discussion and development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , List-Id: Content-Type: text/plain; charset="us-ascii" To: LVM general discussion and development -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Sean McGlynn wrote: > Hello, > > > > I did an fdisk -l to review my partition table (see results below), and > found four entries that end with "Disk /dev/dm-X doesn't contain a valid > partition table." I don't recall seeing this in the past, so I believe > it is something new. Later kernels include dm devices in the list of partitions in proc, so fdisk will attempt to scan them for partition tables. It's not harmful, just noise. > I recently began using kernel 2.6.21.1, up from 2.6.9-42. I don't know > if perhaps this had some effect, or if the entries are normal and I just > never noticed them. If you don't like it & you've not configured anything to use /dev/dm-* devices directly (instead of /dev/mapper/* or /dev//* or whatever) then you can reconfigure udev to not create the dm-* nodes. - From memory, you need to comment out the rule that begins "KERNEL="dm-[0-9]*" in /etc/udev/rules.d/50-udev.rules, or, for newer udevs you can add ignore_device: KERNEL=="dm-[0-9]*", ACTION=="add", OPTIONS+="ignore_device" > > > What led me here is that sar -d output includes four entries for hard > drives (dev253 entries) when there are only three on my system. Fdisk > is reporting four DM devices, so I'm thinking there is some correlation, > but I don't know what. Those "dev253" entries are your device-mapper devices. Take a look at /dev/dm-* with ls -l and you will see that the major number is 253. Kind regards, Bryn. -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.7 (GNU/Linux) Comment: Using GnuPG with Fedora - http://enigmail.mozdev.org iD8DBQFGUayT6YSQoMYUY94RAqJKAJ9dFJtaRg3fONo7kLOkDezcS/FizwCcDwFj 2McvW5Wl+zudmUZDO2aE1fQ= =NHOE -----END PGP SIGNATURE-----