From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marian Csontos Subject: Re: dm_mirror/dm_raid1 limitations ?. Date: Mon, 26 Jan 2015 20:01:54 +0100 Message-ID: <54C68F22.5080004@redhat.com> References: <4d982ea8-3769-46d2-ba73-2d1525faa63b@default> <54C64C4F.6090601@redhat.com> Reply-To: device-mapper development Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; Format="flowed" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: dm-devel-bounces@redhat.com Errors-To: dm-devel-bounces@redhat.com To: dm-devel@redhat.com List-Id: dm-devel.ids On 01/26/2015 04:34 PM, suresh.babu.kandukuru@oracle.com wrote: > Heinzm,thanks for the quick reply.. We are using dmestup create > mirror ..as we want to do that on physical San lun (block devices) > ... Not the one ( lv create ) you mentioned below.. Is there any > advantage going with logical volume approach lvcreate -type One of LVM features is monitoring of mirror/raid LVs and removing/replacing any missing legs. Using dmsetup directly, you have to do this manually. > > /Suresh > > Sent from my iPhone > >> On Jan 26, 2015, at 7:46 PM, Heinz Mauelshagen >> wrote: >> >> >>> On 01/26/2015 02:51 PM, Suresh Babu Kandukuru wrote: Use case is >>> : Two luns are mapped from storage array to linux host which are >>> in same SAN fabric . we want to create a mirror on the linux host >>> with these two luns and let host use that mirror lun . basic >>> tests suggest that dm_mirror working fine . when we have any >>> intermittent path issues with between host and san array , host >>> i/o just freeze , never returns back even after the path is >>> online. >> >> Hard to tell what's happening without any kernel log. >> >>> >>> Is dm_mirror viable solution here ?. Can you point me any link >>> which gives the limitations of dm_mirror ? . another alternate >>> solutions you propose here ?. Thanks in advance . >> >> We've switched the default away from "mirror" to "raid1" in order >> to take advantage of th MD runtime. Have you tested "lvcreate >> --type raid1 ..." yet? Please do. >> >> Regards, Heinz >> >>> >>> Thanks /Suresh >>> >>> >>> -- dm-devel mailing list dm-devel@redhat.com >>> https://www.redhat.com/mailman/listinfo/dm-devel >> >> > > > > -- dm-devel mailing list dm-devel@redhat.com > https://www.redhat.com/mailman/listinfo/dm-devel >