mdadm does not automount on boot / hangs

[donarntz]

Binary package hint: mdadm

Sorry for such a simple report, but I'm a linux newbie. Since doing a clean install of 10.10 desktop, my 2 disk linux raid autodetect raid10 hangs on the skip screen at boot when added to fstab. No system files on the raid, strictly media. Also see http://ubuntuforums.org/showthread.php?t=1468064

ProblemType: Bug
DistroRelease: Ubuntu 10.10
Package: mdadm 2.6.7.1-1ubuntu16
ProcVersionSignature: Ubuntu 2.6.35-22.34-generic 2.6.35.4
Uname: Linux 2.6.35-22-generic x86_64
NonfreeKernelModules: nvidia
Architecture: amd64
CheckboxSubmission: eaed68e67dd1c1d166714deaa95ff394
CheckboxSystem: edda5d4f616ca792bf437989cb597002
Date: Sun Oct 17 13:13:06 2010
InstallationMedia: Ubuntu 10.10 "Maverick Meerkat" - Release amd64 (20101007)
MDadmExamine.dev.sda: Error: command ['/sbin/mdadm', '-E', '/dev/sda'] failed with exit code 1: mdadm: cannot open /dev/sda: Permission denied
MDadmExamine.dev.sda1: Error: command ['/sbin/mdadm', '-E', '/dev/sda1'] failed with exit code 1: mdadm: cannot open /dev/sda1: Permission denied
MDadmExamine.dev.sda2: Error: command ['/sbin/mdadm', '-E', '/dev/sda2'] failed with exit code 1: mdadm: cannot open /dev/sda2: Permission denied
MDadmExamine.dev.sda5: Error: command ['/sbin/mdadm', '-E', '/dev/sda5'] failed with exit code 1: mdadm: cannot open /dev/sda5: Permission denied
MDadmExamine.dev.sdb: Error: command ['/sbin/mdadm', '-E', '/dev/sdb'] failed with exit code 1: mdadm: cannot open /dev/sdb: Permission denied
MDadmExamine.dev.sdb1: Error: command ['/sbin/mdadm', '-E', '/dev/sdb1'] failed with exit code 1: mdadm: cannot open /dev/sdb1: Permission denied
MDadmExamine.dev.sdc: Error: command ['/sbin/mdadm', '-E', '/dev/sdc'] failed with exit code 1: mdadm: cannot open /dev/sdc: Permission denied
MDadmExamine.dev.sdc1: Error: command ['/sbin/mdadm', '-E', '/dev/sdc1'] failed with exit code 1: mdadm: cannot open /dev/sdc1: Permission denied
MachineType: System manufacturer System Product Name
ProcCmdLine: BOOT_IMAGE=/boot/vmlinuz-2.6.35-22-generic root=UUID=0f7a889c-b538-4229-9fbf-69f4e56aae5d ro vga=799 quiet splash
ProcEnviron:
 LANG=en_US.utf8
 SHELL=/bin/bash
ProcMDstat:
 Personalities : [linear] [multipath] [raid0] [raid1] [raid6] [raid5] [raid4] [raid10]
 md0 : active raid10 sdb1[0] sdc1[1]
       976759936 blocks 2 near-copies [2/2] [UU]

 unused devices: <none>
SourcePackage: mdadm
dmi.bios.date: 08/25/2010
dmi.bios.vendor: American Megatrends Inc.
dmi.bios.version: 2301
dmi.board.asset.tag: To Be Filled By O.E.M.
dmi.board.name: M4A78 PLUS
dmi.board.vendor: ASUSTeK Computer INC.
dmi.board.version: Rev X.0x
dmi.chassis.asset.tag: Asset-1234567890
dmi.chassis.type: 3
dmi.chassis.vendor: Chassis Manufacture
dmi.chassis.version: Chassis Version
dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvr2301:bd08/25/2010:svnSystemmanufacturer:pnSystemProductName:pvrSystemVersion:rvnASUSTeKComputerINC.:rnM4A78PLUS:rvrRevX.0x:cvnChassisManufacture:ct3:cvrChassisVersion:
dmi.product.name: System Product Name
dmi.product.version: System Version
dmi.sys.vendor: System manufacturer
etc.blkid.tab:
 <device DEVNO="0x0801" TIME="1287285635" UUID="0f7a889c-b538-4229-9fbf-69f4e56aae5d" TYPE="ext4">/dev/sda1</device>
 <device DEVNO="0x0805" TIME="1287285635" UUID="30c33535-115a-4c55-93a5-9293ae966262" TYPE="swap">/dev/sda5</device>
 <device DEVNO="0x0811" TIME="1287285635" UUID="18c4707f-9f98-dc29-a0ba-7a48c5e43ae1" TYPE="linux_raid_member">/dev/sdb1</device>
 <device DEVNO="0x0821" TIME="1287285636" UUID="18c4707f-9f98-dc29-a0ba-7a48c5e43ae1" TYPE="linux_raid_member">/dev/sdc1</device>
 <device DEVNO="0x0900" TIME="1287285636" PRI="10" LABEL="Krazy Kat" UUID="839aa19b-2940-4683-bfc5-45ecd161c648" TYPE="ext4">/dev/md0</device>

[Hulkie (hulkie2)]

I experience a similar problem. I have a two disk raid-0 configuration as root and sometimes the system boots, sometimes it does not. In my opinion a race-condition at start-up.