UEFI Installation on sdc, Windows 8 partitons on sda gone?

Question

Hi all!
I installed arch on my machine today, now it looks like my windows 8 partitions are gone, maybe someone can help me out.
My setting:
sda Windows 8 uefi installation
sdb ntfs
sdc ntfs and arch uefi installation
So what i did:
I freed up 100GB in sdc for the arch partitions:
[root@chief-pc chief]# sudo gdisk -l /dev/sdc
GPT fdisk (gdisk) version 0.8.7
Partition table scan:
MBR: protective
BSD: not present
APM: not present
GPT: present
Found valid GPT with protective MBR; using GPT.
Disk /dev/sdc: 1953525168 sectors, 931.5 GiB
Logical sector size: 512 bytes
Disk identifier (GUID): C82D4B3F-BE8C-4B1F-B3D6-73ED7B839865
Partition table holds up to 128 entries
First usable sector is 34, last usable sector is 1953525134
Partitions will be aligned on 2048-sector boundaries
Total free space is 2014 sectors (1007.0 KiB)
Number Start (sector) End (sector) Size Code Name
1 2048 1743808511 831.5 GiB 0700 Basic data partition
2 1743808512 1744873471 520.0 MiB EF00 efi
3 1744873472 1753262079 4.0 GiB 8200 swap
4 1753262080 1953525134 95.5 GiB 8300 root
As you can see I made a new efi partition on sdc, because I did not want to touch sda at all.
Then I installed grub:
mount -t vfat /dev/sdc2 /boot/efi
mkdir /boot/efi/EFI
modprobe dm-mod
grub-install --target=x86_64-efi --efi-directory=/boot/efi --bootloader-id=arch_grub --recheck
grub-mkconfig -o /boot/grub/grub.cfg
Everything went fine, I rebooted my system and it automatically booted into grub instead of win8 (win bootloader should have been standard in my asus uefi bios), so I rebooted again and tried to switch back to win bootloader in asus uefi bios, but the win entry was gone.
So back to arch, my output for sda looks like this:
[root@chief-pc chief]# sudo gdisk -l /dev/sda
GPT fdisk (gdisk) version 0.8.7
Partition table scan:
MBR: protective
BSD: not present
APM: not present
GPT: present
Found valid GPT with protective MBR; using GPT.
Disk /dev/sda: 234441648 sectors, 111.8 GiB
Logical sector size: 512 bytes
Disk identifier (GUID): FFB20C3D-64F8-46F9-9504-C591105405FC
Partition table holds up to 128 entries
First usable sector is 34, last usable sector is 234441614
Partitions will be aligned on 2048-sector boundaries
Total free space is 233827181 sectors (111.5 GiB)
Number Start (sector) End (sector) Size Code Name
1 2048 616447 300.0 MiB 2700 Basic data partition
So where are all the win8 partitions? efi, system-reserved and ntfs
I never touched sda during the installation.
Please help me out here
best regards chief

Answer 1

chieffun wrote:
[root@chief-pc chief]# sudo gdisk -l /dev/sda
Disk /dev/sda: 234441648 sectors, 111.8 GiB
Number Start (sector) End (sector) Size Code Name
1 2048 616447 300.0 MiB 2700 Basic data partition
So where are all the win8 partitions? efi, system-reserved and ntfs
I never touched sda during the installation.
First, please verify that this is the correct disk. As Trilby pointed out, disk device names (/dev/sda, /dev/sdb, etc.) can change. There may be a clue in the disk size: 111.8GiB. If both /dev/sda and /dev/sdb were identical, that might not be enough of a clue; but if your disks all had unique sizes, the disk size should tell you which one is which.
Second, the type code 2700 refers to a Windows Recovery Environment (RE) partition. This suggests that this partition is an emergency partition, and the size of 300MiB seems consistent with that. OTOH, the partition name of "Basic data partition" suggests something else. The fact that the  one partition fills far less than the entire disk is not a good sign. You could try using "blkid" on the partition in Linux to see what its filesystem type is, and perhaps mount it to examine its contents.
Finally, try using gdisk's recovery features. You can start with the "-v" option to perform a check on the GPT's integrity. It's conceivable that this will report a problem that you'll then be able to correct in one way or another. You could also play with the options on the gdisk recovery & transformation menu (type "r" at the main menu to get here). In particular, it's conceivable that the "c" option on that menu will help; it loads the backup partition table and uses it in preference to the main one. If you use that option and it restores your partitions, save your changes with "w".
WonderWoofy wrote:The manual nature of the Arch Linux installation means that you (should) know exactly what you are implementing and what it is doing.  So the only way that Arch Linux can wipe out another system is if the administrator (you) wipes them out.
I agree. Some inadvertent action that you haven't reported must be responsible for these problems. It's conceivable that the action was in another distribution's installer or even in Windows.
WonderWoofy wrote:The only thing you can try is to see if you can use some kind of partition recovery software.  There are some out there that can (somewhat reliably) detect where the start and end points of the old partitions were, and regenerate the partition table for you.  The other type of recovery software is those that scan the device and try to recover individual lost files.  Some of them do both.  You should probably start reading up on them.
In Linux, the TestDisk utility can scan for missing partitions, while PhotoRec can scan for lost files. I gather there are better Windows tools for scanning for lost files on NTFS volumes, but I don't happen to have any pointers. TestDisk tends to do a decent job, but it's a bit confusing to the uninitiated, and it can become hopelessly confused if the disk has been repartitioned a lot in the past.
chieffun wrote:So I thought that maybe arch does not like 2 efi partitions in one system and corrupted it somehow.
No, that can't be it. As cfr says, Windows doesn't like multiple ESPs; but that's mostly an issue for the Windows installer. (It tends to get confused and aborts halfway through the installation.) I'm not even sure if Windows misbehaves in this way when the ESPs are on different disks; it might handle that situation OK, for all I know. Windows certainly doesn't go postal on its own partitions if it sees two ESPs. That said, it's conceivable that a Windows bug did cause this problem, if you booted Windows at some point during the process.
chieffun wrote:I also tried to rescue with parted rescue command and gpart, looks like something completely wiped (or corrupted) the partitions away. As if they have never been there in the first place...
In my experience, the partition rescue features of GParted and parted are unreliable at best. TestDisk does a much better job.