When switching the repositories and trying to upgrade from Leap to Tumbleweed as described here: http://www.techrepublic.com/article/how-to-upgrade-opensuse-leap-to-opensuse...
Unfortunately, I trusted in the aforementioned easy-peasy upgrade description and didn't make any backups - as I've previously done similar switches from Debian stable to testing without any serious issues - not counting in the now obvious perils of evil side-effects from lvm installations.
The whole lvm-based system was inaccessible and would get stuck at the Grub boot message. When trying to access and mount the lv's from a live system, it turned out, that the boot partition - if there was one, that is - and the complete home contents were gone, of which at least the last supposedly should have been located inside the sys volume or appearing in the vg as a separate lv. Problem is also, I don't really remember the lvm layout for home, which was generated during installation, and even if there was a separate regular boot partition (but the sys volume actually does contain a boot folder).
Now, only one partition can be found by fdisk, holding a lvm container with the three lv's residing in one volume group, a data exchange volume, a sys volume (root lv) - which is large enough to supposedly also holding the complete home volume, but /home is empty - and a swap volume.
I'd really need to get back the data on home somehow, but:
mount /dev/mapper/lv-sys mnt/sys - the folder inside the sys volume is empty, and no other lv indicating home content can be found.
Testdisk will but find a home folder during a deep scan (unpartitioned search) on the drive - but not finding any files, saying the filesystm might be damaged. Scanning the data exchange partition will give warnings about "number of sectors per track mismatching" on FAT-12 and also revealing traces of a XFS and an ext4 partition, which seem to contain efi boot files, if I mount them to a separate folder. Scanning the sys volume will find traces of a home folder, but trying to list files will only give a "damaged data" message. Mounting sys will give access to /, but, as said, home is empty. Generally, testdisk does not seem to give any useful output. Probably, because the sys lv was set up with btrfs and data lv with xfs, which may not be properly supported by testdisk.
Can you please give some advice, how to escape this mess and retrieve at least the data on home? Recovering the whole system is only a secondary goal.
Many thanks, sawin