From owner-freebsd-scsi@FreeBSD.ORG Fri Mar 26 14:24:58 2010 Return-Path: Delivered-To: freebsd-scsi@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 61E2A1065674 for ; Fri, 26 Mar 2010 14:24:58 +0000 (UTC) (envelope-from mj@feral.com) Received: from ns1.feral.com (ns1.feral.com [192.67.166.1]) by mx1.freebsd.org (Postfix) with ESMTP id 3C1248FC20 for ; Fri, 26 Mar 2010 14:24:57 +0000 (UTC) Received: from [192.168.0.102] (m206-63.dsl.tsoft.com [198.144.206.63]) by ns1.feral.com (8.14.3/8.14.3) with ESMTP id o2QEOvLq040462 for ; Fri, 26 Mar 2010 06:24:57 -0800 (PST) (envelope-from mj@feral.com) Message-ID: <4BACC3C0.4000104@feral.com> Date: Fri, 26 Mar 2010 07:25:04 -0700 From: Matthew Jacob User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.1.8) Gecko/20100227 Thunderbird/3.0.3 MIME-Version: 1.0 To: freebsd-scsi@freebsd.org References: <75a268721003260127o4de50576m512862545fae292d@mail.gmail.com> In-Reply-To: <75a268721003260127o4de50576m512862545fae292d@mail.gmail.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Greylist: Default is to whitelist mail, not delayed by milter-greylist-4.2.3 (ns1.feral.com [192.67.166.1]); Fri, 26 Mar 2010 06:24:57 -0800 (PST) Subject: Re: Asymmetric logical unit access(ALUA) and FreeBSD X-BeenThere: freebsd-scsi@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: SCSI subsystem List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 26 Mar 2010 14:24:58 -0000 On 3/26/2010 1:27 AM, Omer Faruk Sen wrote: > I want to know if FreeBSD supports Asymmetric logical unit access ? > Not as such, no. The only multipath really is at the GEOM layer, which is dead stupid. It should be ALUA aware, but I'll rate it lower than getting the FreeBSD probe code to use REPORT LUNS. > > > From http://www.vicengle.org/san/dmp.php > > ALUA, Asymmetric logical unit access > > ALUA is a relatively new multipathing technology for asymmetrical > arrays. If the array is ALUA compliant and the host multipathing layer > is ALUA aware then virtually no additional configuration is required > for proper path management by the host. An Asymmetrical array is one > which provides different levels of access per port. For example on a > typical Asymmetrical array with 2 controllers it may be that a > particular LUN's paths to controller-0 port-0 are active and optimized > while that LUN's paths to controller-1 port-0 are active > non-optimized. The multipathing layer should then use paths to > controller-0 port-0 as the primary paths and paths to controller-1 > port-0 as the secondary (failover) paths. Sun Solaris 10 MPxIO is an > example of an ALUA aware multipathing solution. A Netapp FAS3020 with > Data ONTAP 7.2.x is an example of an ALUA compliant array. > > > > Regards. > _______________________________________________ > freebsd-scsi@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-scsi > To unsubscribe, send any mail to "freebsd-scsi-unsubscribe@freebsd.org" >