From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christophe Varoqui Subject: Re: Setting up a multipath device Date: Thu, 04 May 2006 20:55:27 +0200 Message-ID: <1146768927.27764.12.camel@localhost.localdomain> References: <445A0AE9.20907@voltaire.com> <20060504144915.GA2319@pundit> <445A1D88.7030500@voltaire.com> Reply-To: device-mapper development Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <445A1D88.7030500@voltaire.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: dm-devel-bounces@redhat.com Errors-To: dm-devel-bounces@redhat.com To: device-mapper development List-Id: dm-devel.ids > > 1. Was it wrong to run 'multipath 2 round-robin 1 0 /dev/sda > round-robin 1 0 /dev/sdb'? The multipath command just don't understand these parameters. This is a map as seen by the DM kernel driver. You can feed it to dmsetup(8), not to multipath(8). > 2. If I don't supply any parameters, how does the dm know which > devices are the same physical device (that /dev/sda & /dev/sdb are > the same physical device)? Because it scans the paths for unique LU ids, then coalesce. > 3. How are the priority groups defined if no parameters are supplied? User defines, through config file. > 4. What is the timeout for a device that has failed? When does the dm > move to the next priority group? > When secondary PG priority becomes higher than the active PG priority, modulo user-define delay or user-define disabling. Or when all paths in the active PG have failed. Regards, cvaroqui