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mdadm array not found on reboot

DISCUSSION Jeffrey B. Layton 3 participants 7 messages May 7, 2007 MD RAID

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Jeffrey B. Layton

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#0 lore raw

Hello,

I apologize if this is a FAQ question or a typical newbie question, but by google efforts have yielded anything yet.

I built a RAID-1 using mdadm (Centos 4.2 with 2.6.16.19 kernel and mdadm 1.6.0-2). It's just two SATA drives that I created using:

mdadm --create --verbose /dev/md1 --level=raid1 --raid-devices=2 /dev/sda1 /dev/sdb1

The md built correctly and I built an ext3 on it. I created /etc/mdadm.conf and modified /etc/fstab to mount the device. But when I reboot, the kernel drops into RAID repair mode because it can't seem to find /dev/md1 and yells about not finding any valid superblock (I can get the exact message if needed). However I can mount /dev/sda1 with no problems.

The only way I can get md1 back is to issue the command:

mdadm -A /dev/md1 /dev/sda1 /dev/sdb1

and everything works. I want to have /dev/md1 mounted automatically on boot. I'm missing something simple here - how do I do this?

TIA!

Jeff

#1 lore raw
Quoted 23 lines · Jeffrey B. Layton

Hello,

I apologize if this is a FAQ question or a typical newbie question, but by google efforts have yielded anything yet.

I built a RAID-1 using mdadm (Centos 4.2 with 2.6.16.19 kernel and mdadm 1.6.0-2). It's just two SATA drives that I created using:

mdadm --create --verbose /dev/md1 --level=raid1 --raid-devices=2 /dev/sda1 /dev/sdb1

The md built correctly and I built an ext3 on it. I created /etc/mdadm.conf and modified /etc/fstab to mount the device. But when I reboot, the kernel drops into RAID repair mode because it can't seem to find /dev/md1 and yells about not finding any valid superblock (I can get the exact message if needed). However I can mount /dev/sda1 with no problems.

The only way I can get md1 back is to issue the command:

mdadm -A /dev/md1 /dev/sda1 /dev/sdb1

and everything works. I want to have /dev/md1 mounted automatically on boot. I'm missing something simple here - how do I do this?

Quoted 9 lines

TIA!

Jeff

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Sounds like a udev issue and/or you did not create the mdadm.conf properly. Show us your mdadm.conf.

#3 lore raw
In reply to Jeffrey B. Layton
Quoted 40 lines · Jeffrey B. Layton
Quoted 31 lines · Justin Piszcz
Quoted 27 lines · Jeffrey B. Layton

Hello,

I apologize if this is a FAQ question or a typical newbie question, but by google efforts have yielded anything yet.

I built a RAID-1 using mdadm (Centos 4.2 with 2.6.16.19 kernel and mdadm 1.6.0-2). It's just two SATA drives that I created using:

mdadm --create --verbose /dev/md1 --level=raid1 --raid-devices=2 /dev/sda1 /dev/sdb1

The md built correctly and I built an ext3 on it. I created /etc/mdadm.conf and modified /etc/fstab to mount the device. But when I reboot, the kernel drops into RAID repair mode because it can't seem to find /dev/md1 and yells about not finding any valid superblock (I can get the exact message if needed). However I can mount /dev/sda1 with no problems.

The only way I can get md1 back is to issue the command:

mdadm -A /dev/md1 /dev/sda1 /dev/sdb1

and everything works. I want to have /dev/md1 mounted automatically on boot. I'm missing something simple here - how do I do this?

TIA!

Jeff

Quoted 8 lines
Quoted 5 lines

-
To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html

Sounds like a udev issue and/or you did not create the mdadm.conf properly. Show us your mdadm.conf.

Quoted 9 lines

ARRAY /dev/md1 level=raid1 num-devices=2 UUID=e235ee6c:415f1494:23c28b59:afd20140
devices=/dev/sda1,/dev/sdb1
ARRAY /dev/md0 level=raid1 num-devices=2 UUID=7121b438:7d36f9f6:8aa9c8b3:b5b0d211
devices=/dev/hdc1,/dev/hdd1

Thanks!

Jeff

What distro?

Checkout my mdadm.conf and look att he auto-create devices option.

# mdadm.conf
#
# Please refer to mdadm.conf(5) for information about this file.
#
# by default, scan all partitions (/proc/partitions) for MD superblocks.
# alternatively, specify devices to scan, using wildcards if desired.
DEVICE partitions
# auto-create devices with Debian standard permissions
CREATE owner=root group=disk mode=0660 auto=yes
# automatically tag new arrays as belonging to the local system
HOMEHOST <system>
# instruct the monitoring daemon where to send mail alerts
MAILADDR root
# definitions of existing MD arrays
ARRAY /dev/md0 level=raid1 num-devices=2 UUID=82009f4a:35cca4ed:b9b6bb73:9360360
7
ARRAY /dev/md1 level=raid1 num-devices=2 UUID=bb7106b3:1645d1e5:201cd0a5:395e2d2
a
ARRAY /dev/md2 level=raid1 num-devices=2 UUID=12473837:fbc2b583:a5c8a649:8695efb
a
ARRAY /dev/md3 level=raid5 num-devices=10 UUID=957d8b7d:c80043bc:083fb634:68e9eb
49

# This file was auto-generated on Sat, 28 Apr 2007 18:59:02 -0400

# by mkconf $Id: mkconf 261 2006-11-09 13:32:35Z madduck $
author
#2 lore raw
In reply to Justin Piszcz
Quoted 31 lines · Justin Piszcz
Quoted 27 lines · Jeffrey B. Layton

Hello,

I apologize if this is a FAQ question or a typical newbie question, but by google efforts have yielded anything yet.

I built a RAID-1 using mdadm (Centos 4.2 with 2.6.16.19 kernel and mdadm 1.6.0-2). It's just two SATA drives that I created using:

mdadm --create --verbose /dev/md1 --level=raid1 --raid-devices=2 /dev/sda1 /dev/sdb1

The md built correctly and I built an ext3 on it. I created /etc/mdadm.conf and modified /etc/fstab to mount the device. But when I reboot, the kernel drops into RAID repair mode because it can't seem to find /dev/md1 and yells about not finding any valid superblock (I can get the exact message if needed). However I can mount /dev/sda1 with no problems.

The only way I can get md1 back is to issue the command:

mdadm -A /dev/md1 /dev/sda1 /dev/sdb1

and everything works. I want to have /dev/md1 mounted automatically on boot. I'm missing something simple here - how do I do this?

TIA!

Jeff

Quoted 8 lines
Quoted 5 lines

-
To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html

Sounds like a udev issue and/or you did not create the mdadm.conf properly. Show us your mdadm.conf.

ARRAY /dev/md1 level=raid1 num-devices=2 UUID=e235ee6c:415f1494:23c28b59:afd20140
devices=/dev/sda1,/dev/sdb1
ARRAY /dev/md0 level=raid1 num-devices=2 UUID=7121b438:7d36f9f6:8aa9c8b3:b5b0d211
devices=/dev/hdc1,/dev/hdd1

Thanks!

Jeff

#5 lore raw
In reply to Jeffrey B. Layton
Quoted 39 lines · Jeffrey B. Layton
Quoted 38 lines · Justin Piszcz
Quoted 33 lines · Jeffrey B. Layton
Quoted 20 lines · Justin Piszcz
Quoted 16 lines · Jeffrey B. Layton

Hello,

I apologize if this is a FAQ question or a typical newbie question, but by google efforts have yielded anything yet.

I built a RAID-1 using mdadm (Centos 4.2 with 2.6.16.19 kernel and mdadm 1.6.0-2). It's just two SATA drives that I created using:

mdadm --create --verbose /dev/md1 --level=raid1 --raid-devices=2 /dev/sda1 /dev/sdb1

The md built correctly and I built an ext3 on it. I created /etc/mdadm.conf and modified /etc/fstab to mount the device. But when I reboot, the kernel drops into RAID repair mode because it can't seem to find /dev/md1 and yells about not finding any valid superblock (I can get the exact message if needed). However I can mount /dev/sda1 with no problems.

Quoted 8 lines
Quoted 6 lines

The only way I can get md1 back is to issue the command:

mdadm -A /dev/md1 /dev/sda1 /dev/sdb1

and everything works. I want to have /dev/md1 mounted automatically on boot. I'm missing something simple here - how do I do this?

Sounds like a udev issue and/or you did not create the mdadm.conf properly. Show us your mdadm.conf.

ARRAY /dev/md1 level=raid1 num-devices=2 UUID=e235ee6c:415f1494:23c28b59:afd20140
devices=/dev/sda1,/dev/sdb1
ARRAY /dev/md0 level=raid1 num-devices=2 UUID=7121b438:7d36f9f6:8aa9c8b3:b5b0d211
devices=/dev/hdc1,/dev/hdd1

Quoted 8 lines
Quoted 1 line

What distro?

CentOS 4.2. I've been reading something about raidautorun. Would help in this case?

Thanks!

Jeff

That is probably what you want-- also technically you don't 'need' to have the partitions set to 0xfd [Linux Raid Auto Detect], but that may help as well.

fdisk -l /dev/sda

Disk /dev/sda: 74.3 GB, 74355769344 bytes
255 heads, 63 sectors/track, 9039 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

   Device Boot      Start         End      Blocks   Id  System
/dev/sda1               1        2090    16787893+  fd  Linux raid autodetect
/dev/sda2   *        2091        2107      136552+  fd  Linux raid autodetect
/dev/sda3            2108        9039    55681290   fd  Linux raid autodetect

Justin.

author
#4 lore raw
In reply to Justin Piszcz
Quoted 32 lines · Justin Piszcz
Quoted 28 lines · Jeffrey B. Layton
Quoted 27 lines · Justin Piszcz
Quoted 22 lines · Jeffrey B. Layton

Hello,

I apologize if this is a FAQ question or a typical newbie question, but by google efforts have yielded anything yet.

I built a RAID-1 using mdadm (Centos 4.2 with 2.6.16.19 kernel and mdadm 1.6.0-2). It's just two SATA drives that I created using:

mdadm --create --verbose /dev/md1 --level=raid1 --raid-devices=2 /dev/sda1 /dev/sdb1

The md built correctly and I built an ext3 on it. I created /etc/mdadm.conf and modified /etc/fstab to mount the device. But when I reboot, the kernel drops into RAID repair mode because it can't seem to find /dev/md1 and yells about not finding any valid superblock (I can get the exact message if needed). However I can mount /dev/sda1 with no problems.

The only way I can get md1 back is to issue the command:

mdadm -A /dev/md1 /dev/sda1 /dev/sdb1

and everything works. I want to have /dev/md1 mounted automatically on boot. I'm missing something simple here - how do I do this?

Quoted 7 lines
Quoted 5 lines
Quoted 1 line

Sounds like a udev issue and/or you did not create the mdadm.conf properly. Show us your mdadm.conf.

ARRAY /dev/md1 level=raid1 num-devices=2 UUID=e235ee6c:415f1494:23c28b59:afd20140
devices=/dev/sda1,/dev/sdb1
ARRAY /dev/md0 level=raid1 num-devices=2 UUID=7121b438:7d36f9f6:8aa9c8b3:b5b0d211
devices=/dev/hdc1,/dev/hdd1

What distro?

CentOS 4.2. I've been reading something about raidautorun. Would help in this case?

Thanks!

Jeff

#6 lore raw
Quoted 2 lines · Jeffrey B. Layton

CentOS 4.2. I've been reading something about raidautorun. Would help in this case?

Try adding:

DEVICE partitions

to the top of your mdadm.conf and:

auto=part

to the end of your /dev/md1 definition.

eg. ARRAY /dev/md1 level=raid1 num-devices=2 UUID=e235ee6c:415f1494:23c28b59:afd20140 devices=/dev/sda1,/dev/sdb1 auto=part

Regards,

Richard