Someone removed the broken Hard Drive from the system and added a working used Hard Drive with the same specs at the same Serial ATA port with the failed Hard Drive.
The system
# uname -a Linux kernel 3.2.0-4-amd64 #1 SMP Debian 3.2.60-1+deb7u1 x86_64 GNU/Linux # cat /etc/debian_version 7.6
Multiple Devices Device(s) Status
~# cat /proc/mdstat
Personalities : [raid1]
md0 : active raid1 sda2[0]
1949474624 blocks super 1.2 [2/1] [U_]
unused devices:
What we are working with?
# grep -v "#" /etc/fstab UUID=a16c558f-47ec-40ca-8989-5e12ce34a5af / ext4 errors=remount-ro 0 1 UUID=7e96f64f-2f0b-40ac-9de2-4b4f3ff95376 none swap sw 0 0 UUID=15ee3ef4-9097-4b04-a154-076972d2f560 none swap sw 0 0 /dev/sdc1 /media/usb0 auto rw,user,noauto 0 0
# blkid /dev/sda2: UUID="fc20fbc0-faef-29d6-9666-35454cbf4447" UUID_SUB="852ff6bf-04a5-bbcd-5b3a-b542a61372a6" LABEL="kernel:0" TYPE="linux_raid_member" /dev/sda5: UUID="7e96f64f-2f0b-40ac-9de2-4b4f3ff95376" TYPE="swap" /dev/md0: UUID="a16c558f-47ec-40ca-8989-5e12ce34a5af" TYPE="ext4" /dev/sdb2: UUID="CEE46C0AE46BF2DF" TYPE="ntfs" LABEL="System Reserved"
# fdisk -l Disk /dev/sda: 2000.4 GB, 2000398934016 bytes 255 heads, 63 sectors/track, 243201 cylinders, total 3907029168 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x00029b1e Device Boot Start End Blocks Id System /dev/sda1 3899215870 3907028991 3906561 5 Extended /dev/sda2 * 2048 3899213823 1949605888 fd Linux raid autodetect /dev/sda5 3899215872 3907028991 3906560 82 Linux swap / Solaris Partition table entries are not in disk order Disk /dev/sdb: 2000.4 GB, 2000398934016 bytes 255 heads, 63 sectors/track, 243201 cylinders, total 3907029168 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 4096 bytes I/O size (minimum/optimal): 4096 bytes / 4096 bytes Disk identifier: 0xdf90f657 Device Boot Start End Blocks Id System /dev/sdb1 * 2048 206847 102400 7 HPFS/NTFS/exFAT /dev/sdb2 206848 409602047 204697600 7 HPFS/NTFS/exFAT /dev/sdb3 409602048 3907024895 1748711424 7 HPFS/NTFS/exFAT Disk /dev/md0: 1996.3 GB, 1996262014976 bytes 2 heads, 4 sectors/track, 487368656 cylinders, total 3898949248 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x00000000It seems like I am going to hose an old windows system drive (sdb).
A look at the superblock information for /dev/sdb
# mdadm --examine /dev/sdb /dev/sdb: MBR Magic : aa55 Partition[0] : 204800 sectors at 2048 (type 07) Partition[1] : 409395200 sectors at 206848 (type 07) Partition[2] : 3497422848 sectors at 409602048 (type 07)
Copy the partition table of sda to sdb
# sfdisk -d /dev/sda | sfdisk --force /dev/sdb
write grub to sdb
# grub-install /dev/sdb Installation finished. No error reported.
look at the new sdb partition table
# fdisk -l /dev/sdb Disk /dev/sdb: 2000.4 GB, 2000398934016 bytes 255 heads, 63 sectors/track, 243201 cylinders, total 3907029168 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 4096 bytes I/O size (minimum/optimal): 4096 bytes / 4096 bytes Disk identifier: 0xdf90f657 Device Boot Start End Blocks Id System /dev/sdb1 3899215870 3907028991 3906561 5 Extended Partition 1 does not start on physical sector boundary. /dev/sdb2 * 2048 3899213823 1949605888 fd Linux raid autodetect /dev/sdb5 3899215872 3907028991 3906560 82 Linux swap / Solaris Partition table entries are not in disk order
Add sdb to the RAID 1 array
# mdadm --add /dev/md0 /dev/sdb2
check MD status
# cat /proc/mdstat
Personalities : [raid1]
md0 : active raid1 sdb2[2] sda2[0]
1949474624 blocks super 1.2 [2/1] [U_]
[>....................] recovery = 0.3% (7625152/1949474624) finish=431.5min speed=75000K/sec
unused devices:
replace failed HD in a degraded linux RAID 1 array
