Public bug reported: I have a dualboot system with Windows 7 And Ubuntu 11.04. There are two raid 0 "volumes" that I configured in the bios. As far as I understand this is a so called Intel Software Raid (isw) fake raid (https://help.ubuntu.com/community/FakeRaidHowto). On the first "Volume" I have 3 partitions: 2 for the operating systems (Windows 7 And Ubuntu 11.04) and one for grub2. On the second "Volume" I have only one partition where I would like to put my media files (movies, music etc).
The bug I found is related to this second raid volume with my media partition. The media partition is 3 terabytes (TB) in size and I therefore chose to use a GPT partition table instead of msdos as msdos only can handle 2TB partitions. The first problem I encountered is that the media partition is not mapped correctly. The volume is found but the partition is not. Take a look at this: [CODE] olof@olof-P55-UD5:~$ ll /dev/mapper total 0 drwxr-xr-x 2 root root 160 2011-05-04 12:03 ./ drwxr-xr-x 18 root root 4820 2011-05-04 10:03 ../ crw------- 1 root root 10, 236 2011-05-04 10:03 control lrwxrwxrwx 1 root root 7 2011-05-04 10:33 isw_dbfdbhchhg_Media -> ../dm-4 lrwxrwxrwx 1 root root 7 2011-05-04 10:33 isw_dbfdbhchhg_OS -> ../dm-0 lrwxrwxrwx 1 root root 7 2011-05-04 10:03 isw_dbfdbhchhg_OS1 -> ../dm-1 lrwxrwxrwx 1 root root 7 2011-05-04 10:03 isw_dbfdbhchhg_OS2 -> ../dm-2 lrwxrwxrwx 1 root root 7 2011-05-04 10:03 isw_dbfdbhchhg_OS3 -> ../dm-3 [/CODE] So what I have done is that I created two raid 0 volumes (using the computer bios). The first volume is isw_dbfdbhchhg_OS. The second volume is isw_dbfdbhchhg_Media. On partition isw_dbfdbhchhg_OS1 I have grub. On partition isw_dbfdbhchhg_OS2 I have Windows 7. On partition isw_dbfdbhchhg_OS3 I have Ubuntu. But as you can see I only have the volume isw_dbfdbhchhg_Media. There are no partitions. Though there should be one. isw_dbfdbhchhg_Media1 is missing. The following verifies that isw_dbfdbhchhg_Media1 is missing: [CODE] olof@olof-P55-UD5:~$ sudo kpartx -l -v /dev/mapper/isw_dbfdbhchhg_Media isw_dbfdbhchhg_Media1 : 0 6442500096 /dev/mapper/isw_dbfdbhchhg_Media 2048 [/CODE] and to add it I can just run: [CODE] sudo kpartx -a -v /dev/mapper/isw_dbfdbhchhg_Media [/CODE] then i can mount it: [CODE] sudo mount -t ntfs /dev/mapper/isw_dbfdbhchhg_Media1 /mnt/media [/CODE] So up till now all is well apart from this partition not getting mapped and mounted automatically. Link to a forum thread where I posted about this: http://ubuntuforums.org/showthread.php?t=1634793 Now for the main issue: If I restart the computer and choose to load ubuntu in grub again I can use kpartx to map the partition and mount it just as described above... BUT: If I restart the computer and load Windows 7 I can see and edit the media partition from there but If I restart and logs into ubuntu it seems that Windows 7 moved the alternative GPT partiontable... when I try to use kpartx this happens: [CODE] olof@olof-P55-UD5:~/Desktop$ sudo kpartx -a -v /dev/mapper/isw_dbfdbhchhg_Media GPT:Primary header thinks Alt. header is not at the end of the disk. GPT:Alternate GPT header not at the end of the disk. GPT: Use GNU Parted to correct GPT errors. add map isw_dbfdbhchhg_Media1 (252:5): 0 6442500096 linear /dev/mapper/isw_dbfdbhchhg_Media 2048 [/CODE] and if I start the program gparted it to whines about something beeing wrong. This is printed to the terminal as the gui for the program opens: [CODE] olof@olof-P55-UD5:~/Desktop$ sudo gparted ====================== libparted : 2.3 ====================== The backup GPT table is not at the end of the disk, as it should be. This might mean that another operating system believes the disk is smaller. Fix, by moving the backup to the end (and removing the old backup)? Not all of the space available to /dev/mapper/isw_dbfdbhchhg_Media appears to be used, you can fix the GPT to use all of the space (an extra 512 blocks) or continue with the current setting? Unable to satisfy all constraints on the partition. [/CODE] Now there is one solution. It looks like this: [CODE] olof@olof-P55-UD5:~/Desktop$ sudo parted /dev/mapper/isw_dbfdbhchhg_Media print Error: The backup GPT table is not at the end of the disk, as it should be. This might mean that another operating system believes the disk is smaller. Fix, by moving the backup to the end (and removing the old backup)? Fix/Ignore/Cancel? Fix Warning: Not all of the space available to /dev/mapper/isw_dbfdbhchhg_Media appears to be used, you can fix the GPT to use all of the space (an extra 512 blocks) or continue with the current setting? Fix/Ignore? Fix Model: Linux device-mapper (striped) (dm) Disk /dev/mapper/isw_dbfdbhchhg_Media: 3299GB Sector size (logical/physical): 512B/512B Partition Table: gpt Number Start End Size File system Name Flags 1 1049kB 3299GB 3299GB ntfs [/CODE] And after this I can map the partition using kpartx. So my guess is that Windows 7 thinks the disk is smaller than what Ubuntu thinks. Therefore Windows 7 moves "The backup GPT table" from the end of the disk to somewhere a bit in. And then Ubuntu does not like the partition anymore and I have to "repair" it using parted. And my first problem can perhaps be related: Why is not the partition detected on system startup? ---Here are some links I found that seems a bit related to my problems: Unable to use NTFS partition in Windows 7 64 bits and GPT secondary table moved http://ubuntuforums.org/showthread.php?t=1490819 Raid Partition Not Being Mapped At Startup http://ubuntuforums.org/showthread.php?t=1634793 How to auto-mount a NTFS RAID partition? http://www.linuxquestions.org/questions/linux-hardware-18/how-to-auto-mount-a-ntfs-raid-partition-769520/ dmraid, missing partitions [solved - not really] http://forums.gentoo.org/viewtopic-p-5875544.html?sid=a785865f52d1de198f598cb71f1819e3 Device Mapper and nVidia Soft RAID0 (dmraid?) http://ubuntuforums.org/showthread.php?t=915898 --- I will post more info on my raid configuration later. ProblemType: Bug DistroRelease: Ubuntu 11.04 Package: parted 2.3-5ubuntu5 ProcVersionSignature: Ubuntu 2.6.38-8.42-generic 2.6.38.2 Uname: Linux 2.6.38-8-generic x86_64 NonfreeKernelModules: nvidia Architecture: amd64 Date: Wed May 4 13:31:08 2011 InstallationMedia: Ubuntu 11.04 "Natty Narwhal" - Release amd64 (20110427.1) ProcEnviron: LANGUAGE=en_US:en LANG=en_US.UTF-8 SHELL=/bin/bash SourcePackage: parted UpgradeStatus: No upgrade log present (probably fresh install) ** Affects: ubuntu Importance: Undecided Status: New ** Tags: amd64 apport-bug natty running-unity -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/777056 Title: Windows 7 moves alternate GTP header to invalid position? -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs