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mdadm "No arrays found in config file or automatically"

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8,534 Views
Last Modified: 2012-05-11
Folks, I have an old Pentium III running Ubuntu Server 8.04 LTS. All running great with a RAID1 array but now its time to upgrade the server.
This morning I removed & installed the same PCI RAID card into the new Server and attached the two SATA RAID1 drives. When I reboot the server fdisk -l sees the drives OK. When I run mdadm --assemble --scan I get the message "No arrays found in config file or automatically" ... What would your next step be to solve this problem ?
Thanks

PS I have made sure no mdadm.config exists !! Should also have mentioned new OS is Ubtunu server 10.10 LTS
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Commented:
As per your above given comment you were having hardware RAID, not the software one so If this the case then you will not have anything with mdadm.

COuld you please show us output of below given command.

# df -Th

# fdisk -l

Author

Commented:
Sorry..I did not explain very well, yes the RAID card is capable of a hardware RAID but I have found mdadm to be very reliable over the life of the old server so I have choosen to stick with mdadm..


=~=~=~=~=~=~=~=~=~=~=~= PuTTY log 2011.04.25 11:10:16 =~=~=~=~=~=~=~=~=~=~=~=

sudo 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: 0x0002f60b

   Device Boot      Start         End      Blocks   Id  System
/dev/sda1   *           1        9328    74920960   83  Linux
/dev/sda2            9328        9730     3227649    5  Extended
/dev/sda5            9328        9730     3227648   82  Linux swap / Solaris

Disk /dev/sdb: 1500.3 GB, 1500301910016 bytes
255 heads, 63 sectors/track, 182401 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: 0x00b200b2

   Device Boot      Start         End      Blocks   Id  System
/dev/sdb1               1      182401  1465136001   fd  Linux RAID autodetect

Disk /dev/sdc: 1500.3 GB, 1500301910016 bytes
255 heads, 63 sectors/track, 182401 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: 0xb8c994a3

   Device Boot      Start         End      Blocks   Id  System
/dev/sdc1               1      182401  1465136001   fd  Linux RAID autodetect


sudo df -Th
Filesystem    Type    Size  Used Avail Use% Mounted on
/dev/sda1     ext4     71G  1.4G   66G   3% /
none      devtmpfs    2.0G  172K  2.0G   1% /dev
none         tmpfs    2.0G     0  2.0G   0% /dev/shm
none         tmpfs    2.0G  260K  2.0G   1% /var/run
none         tmpfs    2.0G     0  2.0G   0% /var/lock
none         tmpfs    2.0G     0  2.0G   0% /lib/init/rw

Commented:
As per the output you have software RAID not the hardware RAID. I have asked for the output of command to confrim which RAID you have and It has been confirmed.

Commented:
Please execute the below given command and update the output.

# mdadm --examine --scan /dev/sdb1 /dev/sdc1

If everything fine then create /etc/mdadm.conf  by redirecting its output.

# mdadm --examine --scan /dev/sdb1 /dev/sdc1 >> /etc/mdadm.conf

Source: http://www.linuxjournal.com/article/8874?page=0,1

Author

Commented:
OK
Done as you suggested...All looked good


cat /proc/mdstat

Personalities : [linear] [multipath] [raid0] [raid1] [raid6] [raid5] [raid4] [ra                                        id10]
md0 : active raid1 sdc1[0] sdb1[1]
      1465135936 blocks [2/2] [UU]

Should I not see the raid rebuilding ?
Commented:
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Author

Commented:
Perfect - Thank you
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