From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Date: Sat, 25 Sep 2004 10:54:28 +0200 From: Lars Marowsky-Bree To: drbd-dev@linbit.com, linux-ha-dev@lists.linux-ha.org Message-ID: <20040925085428.GA4267@marowsky-bree.de> References: <20040924211133.GC3927@marowsky-bree.de> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: Cc: Subject: [Drbd-dev] Re: [Linux-ha-dev] [RFC] (CRM and) DRBD (0.8) states and transistions, recovery strategies List-Id: Coordination of development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On 2004-09-25T01:04:57, Lars Ellenberg said: > > I don't see any difference here between meta-data and backing store > > loss, actually, that complicates things unnecessarily. > > well, DRBD needs to make a difference, because they meta-data storage > and data storage may be physically different devices, and therefore can > fail independently. (ok, single blocks can fail on the same physical > storage independently, too, but this is an other thing) The point I was trying to make is that meta-data loss and backing storage loss can essentially be mapped to a generic local IO failure. The special case where we only loss access to the backing store and not to the meta-data allows us to set a flag there (for whatever use it may be the next time we compare GCs), but then it amounts to the same: Loss of the local storage. I don't see any benefit in keeping the two as distinct failure modes... Sincerely, Lars Marowsky-Brée -- High Availability & Clustering SUSE Labs, Research and Development SUSE LINUX AG - A Novell company