Thread: Software Raid 5 has an empty partition after rebuilding

folks please - newb major headache @ hand (perfect storm situation).

have 3 1tb hdd on ubuntu 11.04 configured software raid 5. data had been copied weekly onto separate off computer hard drive until failed. few days had power outage , after rebooting box wouldn't mount raid. in infinite wisdom entered

mdadm --create -f...

command instead of

mdadm --assemble

, didn't notice travesty had done until after. started array degraded , proceeded building took ~10 hours. after saw that array , running raid not

mean individual drives partitioned (partition type f8 ) md0 device not. realizing in horror have done trying find solutions. pray --create didn't overwrite entire content of hard drivers...

please me out - data that's on drive important , unique.

possible specifying participating hard drives in wrong order can make mdadm overwrite them? when

mdadm --examine --scan

array /dev/md/0 metadata=1.2 uuid=f1b4084a:720b5712:6d03b9e9:43afe51b name=<hostname>:0

interestingly enough name used 'raid' , not host hame :0 appended.

here 'sanitized' config entries:

device /dev/sdf1 /dev/sde1 /dev/sdd1

create owner=root group=disk mode=0660 auto=yes

homehost <system>

mailaddr root


array /dev/md0 metadata=1.2 name=tanserv:0 uuid=f1b4084a:720b5712:6d03b9e9:43afe51b


here output mdstat

cat /proc/mdstat
personalities : [linear] [multipath] [raid0] [raid1] [raid6] [raid5] [raid4] [raid10]
md0 : active raid5 sdd1[0] sdf1[3] sde1[1]
1953517568 blocks super 1.2 level 5, 512k chunk, algorithm 2 [3/3] [uuu]

unused devices: <none>


fdisk shows following:

fdisk -l

disk /dev/sda: 80.0 gb, 80026361856 bytes
255 heads, 63 sectors/track, 9729 cylinders
units = cylinders of 16065 * 512 = 8225280 bytes
sector size (logical/physical): 512 bytes / 512 bytes
i/o size (minimum/optimal): 512 bytes / 512 bytes
disk identifier: 0x000bf62e

device boot start end blocks id system
/dev/sda1 * 1 9443 75846656 83 linux
/dev/sda2 9443 9730 2301953 5 extended
/dev/sda5 9443 9730 2301952 82 linux swap / solaris

disk /dev/sdb: 750.2 gb, 750156374016 bytes
255 heads, 63 sectors/track, 91201 cylinders
units = cylinders of 16065 * 512 = 8225280 bytes
sector size (logical/physical): 512 bytes / 512 bytes
i/o size (minimum/optimal): 512 bytes / 512 bytes
disk identifier: 0x000de8dd

device boot start end blocks id system
/dev/sdb1 1 91201 732572001 8e linux lvm

disk /dev/sdc: 500.1 gb, 500107862016 bytes
255 heads, 63 sectors/track, 60801 cylinders
units = cylinders of 16065 * 512 = 8225280 bytes
sector size (logical/physical): 512 bytes / 512 bytes
i/o size (minimum/optimal): 512 bytes / 512 bytes
disk identifier: 0x00056a17

device boot start end blocks id system
/dev/sdc1 1 60801 488384001 8e linux lvm

disk /dev/sdd: 1000.2 gb, 1000204886016 bytes
255 heads, 63 sectors/track, 121601 cylinders
units = cylinders of 16065 * 512 = 8225280 bytes
sector size (logical/physical): 512 bytes / 512 bytes
i/o size (minimum/optimal): 512 bytes / 512 bytes
disk identifier: 0x000ca948

device boot start end blocks id system
/dev/sdd1 1 121601 976760001 fd linux raid autodetect

disk /dev/dm-0: 1250.3 gb, 1250254913536 bytes
255 heads, 63 sectors/track, 152001 cylinders
units = cylinders of 16065 * 512 = 8225280 bytes
sector size (logical/physical): 512 bytes / 512 bytes
i/o size (minimum/optimal): 512 bytes / 512 bytes
disk identifier: 0x00000000

disk /dev/dm-0 doesn't contain valid partition table

disk /dev/sde: 1000.2 gb, 1000204886016 bytes
255 heads, 63 sectors/track, 121601 cylinders
units = cylinders of 16065 * 512 = 8225280 bytes
sector size (logical/physical): 512 bytes / 512 bytes
i/o size (minimum/optimal): 512 bytes / 512 bytes
disk identifier: 0x93a66687

device boot start end blocks id system
/dev/sde1 1 121601 976760001 fd linux raid autodetect

disk /dev/sdf: 1000.2 gb, 1000204886016 bytes
255 heads, 63 sectors/track, 121601 cylinders
units = cylinders of 16065 * 512 = 8225280 bytes
sector size (logical/physical): 512 bytes / 512 bytes
i/o size (minimum/optimal): 512 bytes / 512 bytes
disk identifier: 0xe6edc059

device boot start end blocks id system
/dev/sdf1 1 121601 976760001 fd linux raid autodetect

disk /dev/md0: 2000.4 gb, 2000401989632 bytes
2 heads, 4 sectors/track, 488379392 cylinders
units = cylinders of 8 * 512 = 4096 bytes
sector size (logical/physical): 512 bytes / 512 bytes
i/o size (minimum/optimal): 524288 bytes / 1048576 bytes
disk identifier: 0x00000000

disk /dev/md0 doesn't contain valid partition table


suggestions?

regards!

mdadm arrays don't typically have partition on them there's no reason it. add filesystem block device. have tried mount /dev/md0 yet? test (if used ext4 filesystem).

code:

sudo mount /dev/md0 /mnt/ cd /mnt ls

typically, create action not destructive , mdadm recognize there's data on disks , recreate metadata array. have copy of previous /etc/mdadm/mdadm.conf/

code:

cat /etc/mdadm/mdadm.conf

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