From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: with ECARTIS (v1.0.0; list xfs); Wed, 03 Sep 2008 07:10:45 -0700 (PDT) Received: from cuda.sgi.com ([192.48.176.15]) by oss.sgi.com (8.12.11.20060308/8.12.11/SuSE Linux 0.7) with ESMTP id m83EAdko000428 for ; Wed, 3 Sep 2008 07:10:39 -0700 Received: from sandeen.net (localhost [127.0.0.1]) by cuda.sgi.com (Spam Firewall) with ESMTP id 34E291232E73 for ; Wed, 3 Sep 2008 07:12:01 -0700 (PDT) Received: from sandeen.net (sandeen.net [209.173.210.139]) by cuda.sgi.com with ESMTP id qnxA5LxFLKh5A6jJ for ; Wed, 03 Sep 2008 07:12:01 -0700 (PDT) Message-ID: <48BE9B2F.30606@sandeen.net> Date: Wed, 03 Sep 2008 09:11:59 -0500 From: Eric Sandeen MIME-Version: 1.0 Subject: Re: REVIEW: Change mkfs.xfs to set primary superblock inodes in ALL secondaries References: In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: xfs-bounce@oss.sgi.com Errors-to: xfs-bounce@oss.sgi.com List-Id: xfs To: Barry Naujok Cc: "xfs@oss.sgi.com" Barry Naujok wrote: > One peculiarity of mkfs.xfs that no-one has yet been able to explain > to me is that all the secondary superblocks do not contain the > primary superblock's root inode, realtime inodes and quota inodes. > > The root inode is stored in the middle and last AG as well to > make things more unexpected. > > The following makes all the secondaries the same as the primary > (other than the global counters). Also looks good to me. I've always wondered, too, if writing a single backup superblock in the last sector(s) of the device at mkfs/growfs time might be sane? When the primary is corrupt you could quickly get the size of the device, seek to the end, read on the last 1k boundary, see if it's a superblock, and use that as the first easily-findable backup. Just a thought :) -Eric