From mboxrd@z Thu Jan 1 00:00:00 1970 From: Benjammin2068 Subject: Re: Best tool to partition Drives with new sector geometry - (WAS: Need Help with crashed RAID5 (that was rebuilding and then had SATA error on another drive)) Date: Sun, 18 Sep 2016 14:58:45 -0500 Message-ID: <4e08d03d-6759-84fd-6467-3bb2d1d9d320@gmail.com> References: <57BBDA5B.3020706@gmail.com> <57BBDC15.5030301@gmail.com> <57BC61F7.8070102@gmail.com> <57BE450B.4030700@gmail.com> <56e86db5-456d-e9c1-339d-ba8903fe5dde@websitemanagers.com.au> <57BE52BC.6040908@gmail.com> <933228e0-bce4-ffad-f48d-034bf89bc07f@websitemanagers.com.au> <57BF9965.1020403@gmail.com> <57C0856D.8050209@youngman.org.uk> <57C32D8E.9030102@gmail.com> <3b008fb0-1fb3-f12f-d973-3657de6e6923@websitemanagers.com.au> <57C38EF5.7020005@gmail.com> <57C41A47.5050506@youngman.org.uk> <484e25ca-0a8e-f666-b1c8-ebc92a49f999@gmail.com> <57DEE853.4060001@youngman.org.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <57DEE853.4060001@youngman.org.uk> Sender: linux-raid-owner@vger.kernel.org To: Wols Lists , Chris Murphy Cc: Linux-RAID List-Id: linux-raid.ids On 09/18/2016 02:17 PM, Wols Lists wrote: > > I'm sure you know this, but getting the physical/logical block size > out-of-sync hurts disk performance. And copying a smaller partition into > a larger allocated space is perfectly harmless. So... > > I'd simply use a modern partition manager (such as gdisk) to partition > your new drives such that the new partitions are larger than the > existing ones, and are properly aligned relative to the drive geometry. > > Then copy the old partitions across however you were planning - whether > it's "mdadm --replace" or stopping the array and "dd old-device > new-device" or whatever. > > If you've got a bit of wasted space, or whatever, who cares. > You can resize your file-systems to use all available space, if you wish > (can't remember how, whenever I've done that sort of stuff it hasn't > been hard). > > But I'd certainly try and avoid those offset warnings - it smacks to me > of a mismatch between 512-byte blocks and 4K disk sectors, and I > wouldn't want the drive firmware messing about correcting mismatches > between OS 4K blocks and drive 4K blocks. I don't fully understand it > but I know there was a lot of grief with exactly this sort of thing in > the transition from 512-byte to 4K. > Aha! That's what I needed to know. I was wondering if I can make a partition (I think) that's 3/4 of a block larger (3072bytes) than the original /dev/sdX1's on the old HD103SJs drives. You've answered my question perfectly. I can use sfdisk or parted to get that done... Thanks a bunch! -Ben