From owner-freebsd-geom@FreeBSD.ORG Thu May 10 16:38:28 2012 Return-Path: Delivered-To: freebsd-geom@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 4153B106564A for ; Thu, 10 May 2012 16:38:28 +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 18B078FC21 for ; Thu, 10 May 2012 16:38:28 +0000 (UTC) Received: from [172.16.1.34] (float34.in1.lcl [172.16.1.34]) (authenticated bits=0) by ns1.feral.com (8.14.4/8.14.4) with ESMTP id q4AGcQ8h063177 (version=TLSv1/SSLv3 cipher=DHE-RSA-CAMELLIA256-SHA bits=256 verify=NO) for ; Thu, 10 May 2012 09:38:26 -0700 (PDT) (envelope-from mj@feral.com) Message-ID: <4FABEEFD.90009@feral.com> Date: Thu, 10 May 2012 09:38:21 -0700 From: Matthew Jacob Organization: Feral Software User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:12.0) Gecko/20120428 Thunderbird/12.0.1 MIME-Version: 1.0 To: freebsd-geom@freebsd.org References: <4FABE1A8.4000609@FreeBSD.org> In-Reply-To: <4FABE1A8.4000609@FreeBSD.org> Content-Type: text/plain; charset=KOI8-R; format=flowed Content-Transfer-Encoding: 7bit X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.2.7 (ns1.feral.com [192.67.166.1]); Thu, 10 May 2012 09:38:26 -0700 (PDT) Subject: Re: Teaching gmultipath about path cost/priority X-BeenThere: freebsd-geom@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list Reply-To: mj@feral.com List-Id: GEOM-specific discussions and implementations List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 10 May 2012 16:38:28 -0000 On 5/10/2012 8:41 AM, Alexander Motin wrote: > Hi. > > > It'd be ideal if there was a way of teaching gmultipath about a path > > cost/priority, so that it can make an informed decision about which > > path to choose a) when first initializing, and b) during failover. > > The problem with this is how to store that in metadata. As soon as all > paths have exactly the same metadata and provider names are not > mentioned there, separate paths properties are not possible at this > moment. > > As dirty workaround, you may periodically run some script to enforce > active path on your specific preference. > That is in fact exactly how we did this at Panasas