-----Original Message----- From: centos-bounces at centos.org [mailto:centos-bounces at centos.org] On Behalf Of Scott Silva Sent: Thursday, October 05, 2006 11:15 PM To: centos at centos.org Subject: [CentOS] Re: Cannot re-make a software raid pair Nigel Kendrick spake the following on 10/5/2006 12:45 PM: > Apologies if you get this twice - the first one didn't seem to make it... > > Hi Guys, > > I have just replaced a faulty Max...woah, wait...this one's a > Seagate... IDE hard disk but I cannot remake the software raid pair. > > The currently running disk is hda and I am trying to add back hdg - > both are master drives on separate controllers. > > I have run fdisk on hdg and created the same partition structure as > had and changed their types to 'fd' but when I try and rebuild the array I get: > > mdadm /dev/md0 -a /dev/hdg1 > > mdadm: hot add failed for /dev/hdg1: Invalid argument > > If I look at /var/log/messages, I have: > > Oct 5 16:04:39 petdoctors kernel: md: could not bd_claim hdg1. > Oct 5 16:04:39 petdoctors kernel: md: error, md_import_device() > returned > -16 > >>From other postings, this seems to imply the hdg1 partition is mounted >>but I > can find no evidence of this (df or cat /proc/mounts or lsof). I have > done sone googling and found others having fun with this but no > specific solution. > > Anyone? Maybe the table didn't get re-read after fdisk was done. I usually use sfdisk just because I can copy a partition table without making my usual fat-fingered typos. Are you sure that the new drive isn't smaller than the old? Even by a few cylinders. -- Hi Scott, Disks are 100% identical - right down to the last cylinder...hda is the live disk and hdg is the new one... [root at petdoctors ~]# sfdisk --no-reread /dev/hda Disk /dev/hda: 24321 cylinders, 255 heads, 63 sectors/track Old situation: Units = cylinders of 8225280 bytes, blocks of 1024 bytes, counting from 0 Device Boot Start End #cyls #blocks Id System /dev/hda1 * 0+ 12 13- 104391 fd Linux raid autodetect /dev/hda2 13 273 261 2096482+ 82 Linux swap /dev/hda3 274 24320 24047 193157527+ fd Linux raid autodetect /dev/hda4 0 - 0 0 0 Empty Input in the following format; absent fields get a default value. <start> <size> <type [E,S,L,X,hex]> <bootable [-,*]> <c,h,s> <c,h,s> Usually you only need to specify <start> and <size> (and perhaps <type>). /dev/hda1 : [root at petdoctors ~]# sfdisk /dev/hdg Checking that no-one is using this disk right now ... OK Disk /dev/hdg: 24321 cylinders, 255 heads, 63 sectors/track Old situation: Units = cylinders of 8225280 bytes, blocks of 1024 bytes, counting from 0 Device Boot Start End #cyls #blocks Id System /dev/hdg1 0+ 12 13- 104391 fd Linux raid autodetect /dev/hdg2 13 273 261 2096482+ 82 Linux swap /dev/hdg3 274 24320 24047 193157527+ fd Linux raid autodetect /dev/hdg4 0 - 0 0 0 Empty Input in the following format; absent fields get a default value. <start> <size> <type [E,S,L,X,hex]> <bootable [-,*]> <c,h,s> <c,h,s> Usually you only need to specify <start> and <size> (and perhaps <type>). /dev/hdg1 : [root at petdoctors ~]# mdadm /dev/md1 -a /dev/hdg3 mdadm: hot add failed for /dev/hdg3: Invalid argument [root at petdoctors ~]#