From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ram Ramesh Subject: Re: Can I replace raid6 disk using dd? Date: Tue, 19 Aug 2014 08:42:59 -0500 Message-ID: <53F35463.50204@gmail.com> References: <53F2B6D8.4030208@shiftmail.org> <53F2BB43.4030408@gmail.com> <53F2F82E.7070204@megasoft.be> <53F313FA.5040106@shiftmail.org> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <53F313FA.5040106@shiftmail.org> Sender: linux-raid-owner@vger.kernel.org To: Ethan Wilson Cc: linux-raid List-Id: linux-raid.ids On 08/19/2014 04:08 AM, Ethan Wilson wrote: > On 19/08/2014 09:09, Killian De Volder wrote: >> No need to remove the bitmap. >> But be very careful that the disk is exactly the same size (or bigger). >> I recently had a disk that was slightly smaller then advertised ! >> >> But if it's a raid6 why not just jank a disk ? >> It's still going to be redundant, but only on 1 disk. >> >> Killian De Volder >> Megasoft bvba >> killian.de.volder@megasoft.be >> > > I think it would not be accepted by MD if the size was smaller than > needed. At least with --replace. With the dd thing I don't know: it > might trust the metadata and bypass the check.... I'd be careful in > that case indeed. > -- > To unsubscribe from this list: send the line "unsubscribe linux-raid" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html Thank you all. I think many feel dd is risky although doable. I felt the same way too. Let me look for alternate/safe ways. I wanted to experiment because the real data in the array is small and I had good backups. Still, I do not think it is worth risking the chance of trashing the array. I am more worried of the what if scenario, where there is corruption, but not detected until my backup is no longer up to date - I am not fond of Murphy :-) Ramesh