From mboxrd@z Thu Jan 1 00:00:00 1970 From: Kent Overstreet Subject: Re: Converting existing partition to bcache backing device without loss of data Date: Thu, 8 Aug 2013 17:36:57 -0700 Message-ID: <20130809003657.GF15409@kmo-pixel> References: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: Sender: linux-bcache-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Adam Brenner , g2p.code-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org Cc: linux-bcache-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-bcache@vger.kernel.org On Thu, Aug 08, 2013 at 09:27:33AM -0700, Adam Brenner wrote: > Howdy, > > I am in the process of testing bcache on our HPC cluster to act as > cache for our gluster storage (~750TB). > > I notice that during the setup process on our test cluster, our > backing device (where all our data is stored) will need to be > formatted in order to support bcache. > > Does a way exist so we do not have to format our backing device? Or is > working being done to support this? Unfortunately, there's no general purpose way - the faq explains why (I just fixed the wiki so it's there again :) http://bcache.evilpiepirate.org/FAQ/ However, Gabriel de Perthuis has a tool to do in place conversion - I can't remember if it was limited to lvm devices or not - Gabriel, what was the link to that again? I should stick a link to it in the wiki or give you an account on it so you can.