From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mx2.redhat.com (mx2.redhat.com [10.255.15.25]) by int-mx2.corp.redhat.com (8.13.1/8.13.1) with ESMTP id l1JDUfQn016995 for ; Mon, 19 Feb 2007 08:30:41 -0500 Received: from ciao.gmane.org (main.gmane.org [80.91.229.2]) by mx2.redhat.com (8.13.1/8.13.1) with ESMTP id l1JDUd1X032308 for ; Mon, 19 Feb 2007 08:30:40 -0500 Received: from list by ciao.gmane.org with local (Exim 4.43) id 1HJ8b5-0001UM-Rv for linux-lvm@redhat.com; Mon, 19 Feb 2007 14:30:28 +0100 Received: from 202.3.112.4 ([202.3.112.4]) by main.gmane.org with esmtp (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Mon, 19 Feb 2007 14:30:27 +0100 Received: from rrs by 202.3.112.4 with local (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Mon, 19 Feb 2007 14:30:27 +0100 From: Ritesh Raj Sarraf Date: Mon, 19 Feb 2007 18:33:50 +0530 Message-ID: Mime-Version: 1.0 Content-Transfer-Encoding: 7Bit Sender: news Subject: [linux-lvm] LVM + Multipath 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: linux-lvm@redhat.com Hi, I have a question regarding the combination of LVM + Multipathing in a SAN environment. I have a LUN mapped to a host using iSCSI. I have two two paths to the LUN. This setup, using multipathing, provides me failover functionality. My question is how does LVM react to path failures ? In a failover environment, multipathing can take upto 120 seconds to detect that the active path to the LUN is no more available and then switch to the secondary path. During this 120 seconds, how does LVM react ? Does it really sense that the device is offlined ? Or that information is never passed to LVM and it just allows I/O to happen leaving that responsibility to the multipathing layer ? Thanks, Ritesh -- Ritesh Raj Sarraf RESEARCHUT - http://www.researchut.com "Necessity is the mother of invention." "Stealing logic from one person is plagiarism, stealing from many is research." "The great are those who achieve the impossible, the petty are those who cannot - rrs"