From mboxrd@z Thu Jan 1 00:00:00 1970 From: Roy Sigurd Karlsbakk Subject: Re: AARGH! Please help. IDE controller fsckup Date: Thu, 3 Oct 2002 15:13:28 +0200 Sender: linux-raid-owner@vger.kernel.org Message-ID: <200210031513.28459.roy@karlsbakk.net> References: <200210021516.46668.roy@karlsbakk.net> <200210031225.11283.roy@karlsbakk.net> <20021003114020.GD7350@unthought.net> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: <20021003114020.GD7350@unthought.net> To: Jakob Oestergaard Cc: Kernel mailing list , linux-raid@vger.kernel.org List-Id: linux-raid.ids > > I have used presistent superblocks, but md0,1,2,3 will be different= ly > > ordered if I change the disk order... At least I think so. It surel= y > > didn't work. > > No. md0 would stay md0. This is another effect of using superblocks, > and in fact this is also (ironically) more or less the only argument > *against* using them :) > > (Imagine inserting a disk which knows that it is disk 0 of md0 into s= ome > machine that already has a perfectly fine md0 running) ok. so. theoretically - as long as the system finds all 16 drives, I sh= ould be=20 able to shuffle them around and attach them to whichever controller the= re is?=20 right? ok. now, I've replaced the faulty controller, and booting up. the new contr= oller=20 is also (like the old one) a CMD649... h=E6? it works. but it surely didn't work last time... thanks > > But ... with persistent superblock - is it possible to fsckup the r= aid? > > You're root, it is indeed possible :) er - yes. I more meant like 'automagically' > But you would not need to perform any of the special operations that = you > need to now. > > Persistent superblocks saves you from a number of "bad" situations yo= u > can encounter with normal production systems (such as replacing a > controller or moving disks around). > > One should be careful when moving disks with persistent superblocks > between systems though. You don't want the kernel to autodetect the > "wrong" md0 on boot :) I consider this problem nonexistent in th= e > production environment that I administer, but I know that some people > feel differently about it. You should consider these pros and cons i= n > relation to your environment and make a decision based on that. --=20 Roy Sigurd Karlsbakk, Datavaktmester ProntoTV AS - http://www.pronto.tv/ Tel: +47 9801 3356 Computers are like air conditioners. They stop working when you open Windows. - To unsubscribe from this list: send the line "unsubscribe linux-raid" i= n the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html