From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tomasz Chmielewski Subject: Re: how to synchronize two devices (RAID-1, but not really?) Date: Tue, 15 May 2007 12:41:36 +0200 Message-ID: <46498E60.9060407@wpkg.org> References: <4649760A.1060805@wpkg.org> <17993.34959.150157.200536@notabene.brown> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <17993.34959.150157.200536@notabene.brown> Sender: linux-raid-owner@vger.kernel.org To: Neil Brown Cc: linux-raid@vger.kernel.org List-Id: linux-raid.ids Neil Brown schrieb: (...) > An external bitmap means that if the link goes down, it keeps track of > which blocks are in sync and which aren't, and when the link comes > back up you re-add the missing device and the rebuild continues where > it left off. > mdadm --build /dev/md22 --level=1 --bitmap=/root/mybitmap \ > --write-behind --raid-disks=2 /dev/localdevice --write-mostly /dev/remotedevice One more question - is there a way to estimate the size of the bitmap file? Does it depend on the size of the array? What bitmap file size can I expect for a 600 GB array? -- Tomasz Chmielewski http://wpkg.org