From mboxrd@z Thu Jan 1 00:00:00 1970 From: Hannes Reinecke Subject: Re: [dm-devel] What is the deal with the partition separator? Date: Thu, 17 Feb 2011 08:29:57 +0100 Message-ID: <4D5CCE75.5090202@suse.de> References: <4D5B42BE.3050301@cfl.rr.com> <4D5B7ED9.20304@suse.de> <4D5C2793.1020601@cfl.rr.com> Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Return-path: In-Reply-To: <4D5C2793.1020601-3tLf1voIkJTQT0dZR+AlfA@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: parted-devel-bounces+gcgpd-parted-devel=m.gmane.org-XbBxUvOt3X2LieD7tvxI8l/i77bcL1HB@public.gmane.org Errors-To: parted-devel-bounces+gcgpd-parted-devel=m.gmane.org-XbBxUvOt3X2LieD7tvxI8l/i77bcL1HB@public.gmane.org To: Phillip Susi Cc: device-mapper development , serge.hallyn-GeWIH/nMZzLQT0dZR+AlfA@public.gmane.org, parted-devel-XbBxUvOt3X2LieD7tvxI8l/i77bcL1HB@public.gmane.org, Debian LVM Team List-Id: dm-devel.ids On 02/16/2011 08:37 PM, Phillip Susi wrote: > On 2/16/2011 2:38 AM, Hannes Reinecke wrote: >> The linux scheme since the dawn of time is to >> a) Add the partition number to the device node name >> b) If last letter of the device node name is a number, insert a 'p' >> between device node name and partition number > = > Since the dawn of time? Before device mapper it wasn't possible to have > a disk device name ending in a digit. > = Unless you happen to have a raid HBA, which has names like cciss/c0d0 or rd/c0d0 and, of course, you can have partitions on md devices, too, which will also give you names like md0p1 >> with the advent of persistent device names (via udev) the partition >> separator (for persistent links only!) is '-part'. >> >> So you have >> >> /dev/sda >> /dev/sda1 >> /dev/disk/by-id/scsi-0WhatAStupidName >> /dev/disk/by-id/scsi-0WhatAStupidName-part1 >> >> persistent device names are longish anyway, so we can as well use >> something readable for partitions. > = > That's fine for the symlinks in by-id, but what about the names in > /dev/mapper and /dev/VG? > = /dev/mapper contains the names of the device-mapper devices themselves; for those I don't have any preference. kpartx as called from udev is using the '-part' suffix here, too. Cheers, Hannes -- = Dr. Hannes Reinecke zSeries & Storage hare-l3A5Bk7waGM@public.gmane.org +49 911 74053 688 SUSE LINUX Products GmbH, Maxfeldstr. 5, 90409 N=FCrnberg GF: Markus Rex, HRB 16746 (AG N=FCrnberg)