From mboxrd@z Thu Jan 1 00:00:00 1970 From: Hannes Reinecke Subject: Re: Configuring multipath for root device Date: Mon, 07 Jan 2008 08:38:01 +0100 Message-ID: <4781D6D9.5030204@suse.de> References: <110b17190712191302o60d521eaj693410c26d07c1ad@mail.gmail.com> <1198099093.26366.32.camel@linuxchandra> Reply-To: device-mapper development Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Return-path: In-Reply-To: <1198099093.26366.32.camel@linuxchandra> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: dm-devel-bounces@redhat.com Errors-To: dm-devel-bounces@redhat.com To: sekharan@us.ibm.com, device-mapper development List-Id: dm-devel.ids Chandra Seetharaman wrote: > I am working on a multipath usage document. Attached is the installatio= n > section of that document. >=20 > Note that it is written for RHEL5 U1 and SLES10 SP1. >=20 > Good Luck, >=20 > chandra >=20 > On Wed, 2007-12-19 at 13:02 -0800, Pradipmaya Maharana wrote: >> Hi All, >> >> Is there a process/document that talks about how to configure >> root/boot device for multipath? >> >> Thanks and Regards, >> Pradipmaya. >> >> -- >> dm-devel mailing list >> dm-devel@redhat.com >> https://www.redhat.com/mailman/listinfo/dm-devel >> >> ----------------------------------------------------------------------= -- >> >> 4.1. Installation instructions for SLES10 >> >> Note: This is tested on SLES10 SP1. If you have any other version, you= r >> mileage may vary. >> >> 1. Install the OS in a device that has multiple paths. Make sure th= e >> root device's "Mount by" option is set to "Device by-id" (this option = is >> available under "expert partitioner" as "fstab options"). >> 2. Complete the installation. Let the system boot up in multiuser m= ode. >> Make sure the root device, swap device are all referenced by their by-= id >> device node entries instead of /dev/sd* type names. If they are not, f= ix >> them first. >> 3. Once booted, update /etc/multipath.conf If you have to make chan= ges >> to /etc/multipath.conf, make the changes. >> Note: the option "user_friendly_names" is not supported by initr= d. >> So, if you have user_friendly_names in your /etc/multipath.conf file, >> comment it for now, you can uncomment it later. >> 4. Enable multipathing by running the following commands >> * chkconfig boot.multipath on >> >> * chkconfig multipathd on=20 >> 5. Add multipath module to initrd >> >> Edit the file /etc/sysconfig/kernel and add "dm-multipath" to >> INITRD_MODULES". Note: If your storage devices needs a hardware handle= r, >> add the corresponding module to INITRD_MODULES, in addition to >> "dm-multipath". For example add "dm-rdac" and "dm-multipath" to suppor= t >> IBM's DS4K storage devices >> 6. Run mkinitrd >> Note: You can uncomment the user friendly name if you have comme= nted it above. >> 7. Reboot=20 >> >> The system will come up with the root disk on a multipathed device. >> >> Note: You can switch off multipathing to the root device by adding >> multipath=3Doff to the kernel command line. >> ACK. This is the correct way. Thanks for writing this up. Cheers, Hannes --=20 Dr. Hannes Reinecke zSeries & Storage hare@suse.de +49 911 74053 688 SUSE LINUX Products GmbH, Maxfeldstr. 5, 90409 N=FCrnberg GF: Markus Rex, HRB 16746 (AG N=FCrnberg)