Andrei, et al -- ...and then Andrei Borzenkov said... % On 29.10.2022 05:57, David T-G wrote: % % > This is what my working machine, with a single boot SSD and a mirrored % > pair of data disks, said: % > % > ============================= Boot Info Summary: =============================== % > => Grub2 (v2.00) is installed in the MBR of /dev/sda and looks at sector % > 105657120 of the same hard drive for core.img. core.img is at this ... % % As you see, grub2 is detected as v2.00 and the content of core.img is % parsed. % % % > GUID Partition Table detected. ... % > I wonder if the "B" flag (which, curiously, is on the "next" rather than "curr" % > slice) suggests anything. % % This flag is not used by grub2 anyway. I believe it is used by syslinux % gptmbr code (may be there are other bootloaders that use it). OK. Just digging :-) % % > This is what the dead machine, with sda boot SSD and new sde mirror SSD and % > lots of data disks, said: % > % > ============================= Boot Info Summary: =============================== % > => Grub2 (v1.99) is installed in the MBR of /dev/sda and looks at sector % > 69344384 of the same hard drive for core.img. core.img is at this location. % % As you see it is detected as v1.99 which is wrong version for your Leap % release. Also it does not show the content of core.img. While this can be % due to bug in bootinfoscript, this also suggests that MBR contains old But ... but ... Why the wrong version? They are both the same and they were installed from the same media! Back in September in Message-ID: <20220912035409.GH7367@jpo> I listed the info for all three machines: I'm running Leap 15.x on various computers davidtg@jpo:~> for H in jpo diskfarm gezebel ; do echo $H ; ssh $H " egrep '^(NAME|VERSION)' /etc/os-release " ; echo '' ; done jpo NAME="openSUSE Leap" VERSION="15.2" VERSION_ID="15.2" diskfarm NAME="openSUSE Leap" VERSION="15.2" VERSION_ID="15.2" gezebel NAME="openSUSE Leap" VERSION="15.1" VERSION_ID="15.1" Note the 15.2 on jpo (the "working" one above") as well as diskfarm (the "dead" one in question). Could I upgrade grub2, even though it was working previously and so probably isn't too terribly wrong, from a rescue system? % content and points to disk location where there is no valid core.img. % bootinfoscript just looks for known signatures in the first sector of this % location. May be this sector is still valid. OK. I'm also at this point willing to abandon sda and install on sde from scratch, but this is good to know. % % You can try to find out the the exact disk block of /boot/grub2/core.img on % this disk. Something like % % bor@bor-Latitude-E5450:~$ sudo filefrag -v /boot/grub/x86_64-efi/core.efi ... % % File offset on partition is shown in physical_offset column and is 58993088 % blocks of size 4096. Each block is 8 x 512 sectors. Fun! I'll be filing this away. Thanks! % % In my case /boot is on /dev/sda4, so % % bor@bor-Latitude-E5450:~$ LC_ALL=C sudo fdisk -l /dev/sda % ... % Units: sectors of 1 * 512 = 512 bytes % ... % Device Start End Sectors Size Type % ... % /dev/sda4 7399424 943667199 936267776 446.4G Linux filesystem % % /dev/sda4 starts at sector 7399424 so the absolute disk offset of the file % in sectors is % % 7399424 + 58993088*8 == 479344128 OK. % % Compare the result with bootinfoscript output (looks at sector 70108480 of % the same hard drive for core.img). Do they match? OK. I'll do this when I'm back. Good to know. % ... % > => Grub2 (v1.99-2.00) is installed in the MBR of /dev/sde and looks at sector % > 70108480 of the same hard drive for core.img, but core.img can not be % > found at this location. % % Again, this could be the old installation in MBR. In this case even the % first sector has the wrong (at least, unknown) content. [snip] This drive was brand new in the box when I installed it, and I used the 15.2 installation thumb drive. I don't know why it's 1.99-2.00 and I don't know why it's different from the existing working jpo /dev/sda nor the existing broken diskfarm /dev/sda. Definitely confusing *sigh* Thanks again & HAND :-D -- David T-G See http://justpickone.org/davidtg/email/ See http://justpickone.org/davidtg/tofu.txt