Theo and Dan, Thanks for the info. I've associated the pairs now. Regards, Shan Jing Unix Group - Americas Deutsche Bank 2 Gatehall Drive, 3rd Floor Parsippany, New Jersey, USA shan.jing@db.com 973.682.3463 <Dan_Caulfield@De ll.com> To: <linux-lvm@redhat.com> Sent by: cc: <linux-lvm-bounces@redhat.com> linux-lvm-bounces Subject: RE: How to associate two paths for each EMC device? @redhat.com 03/19/2004 03:43 PM Please respond to LVM general discussion and development This is normal behavior for multipath devices. The OS will "see" the 22 luns on all available paths. The is the way EMC PowerPath, Veritas DMP and LVM work. Each of these products rely on the OS detecting all available paths to the luns. EMC PowerPath uses the device the Symmetrix pdev id of each lun to identify multiple paths to a device. LVM will use the PV UUIDs to identify the multipath devices. For EMC arrays, there is a version of inq that will run on Linux. You will just need to make enough sg devices for it to recognize all 44 devices. The inq utility will help you to determine which pdev is associated to which sd device. See EMC Powerlink Doc emc59180 for all of the details. Regards, Dan -----Original Message----- From: linux-lvm-bounces@redhat.com [mailto:linux-lvm-bounces@redhat.com] On Behalf Of Shan Jing Sent: Friday, March 19, 2004 1:01 PM To: LVM general discussion and development Cc: LVM general discussion and development; linux-lvm-bounces@redhat.com Subject: Re: How to associate two paths for each EMC device? The very basic way to identify the pair is to lvm each of the first 22 luns in a sequence and see which lun in the other 22 set is also lvm'ed. However, there must be a more technical way to resolve this and eventually make the disk represent only once. Any guru out there can help? Regards, Shan Jing Unix Group - Americas Deutsche Bank 2 Gatehall Drive, 3rd Floor Parsippany, New Jersey, USA shan.jing@db.com 973.682.3463 Theo Van Dinter <felicity@kluge.n To: LVM general discussion and development <linux-lvm@redhat.com> et> cc: Sent by: Subject: Re: How to associate two paths for each EMC device? linux-lvm-bounces @redhat.com 03/19/2004 12:44 PM Please respond to LVM general discussion and development On Fri, Mar 19, 2004 at 12:21:51PM -0500, Shan Jing wrote: > I have 22 EMC symmetrix disks on two HBA links. At this moment, there is no working copy of EMC powerpath or HP Securepath available for my kernel (2.4.21-112-itanium2-smp); therefore, I have to use the luns directly with lvm without any DMP software in the middle. > > Without DMP software, there are two set of 22 luns, each representing one HBA path. See blow. Can you set your HBA driver to do failover? ie: something like this in modules.conf: options qla2300 ql2xfailover=1 ql2xmaxqdepth=64 This works well for my servers connected to a CX-series array. :) The driver handles failing between HBAs (active-passive), and only has the LUN presented once to the system. -- Randomly Generated Tagline: "I didn't know Allman was a stand-up comedian ..." - Theo about laughter from sendmail tutorial _______________________________________________ linux-lvm mailing list linux-lvm@redhat.com https://www.redhat.com/mailman/listinfo/linux-lvm read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/ The following file(s) have been deleted by: Shan Jing on 3/19/2004 1:58:20 PM C.DTF attq5vht.dat -- This e-mail may contain confidential and/or privileged information. If you are not the intended recipient (or have received this e-mail in error) please notify the sender immediately and destroy this e-mail. Any unauthorized copying, disclosure or distribution of the material in this e-mail is strictly forbidden. _______________________________________________ linux-lvm mailing list linux-lvm@redhat.com https://www.redhat.com/mailman/listinfo/linux-lvm read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/ _______________________________________________ linux-lvm mailing list linux-lvm@redhat.com https://www.redhat.com/mailman/listinfo/linux-lvm read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/ -- This e-mail may contain confidential and/or privileged information. If you are not the intended recipient (or have received this e-mail in error) please notify the sender immediately and destroy this e-mail. Any unauthorized copying, disclosure or distribution of the material in this e-mail is strictly forbidden. _______________________________________________ linux-lvm mailing list linux-lvm@redhat.com https://www.redhat.com/mailman/listinfo/linux-lvm read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/