Hi Valdikss, On Sat, Jul 08, 2023 at 09:17:54PM +0300, ValdikSS wrote: >Hello list, > >I was getting very slow boot speeds on old WYSE C10LE thin client with VIA C7 >CPU and Phoenix bios (year 2008). This is due to combination of BIOS, GRUB, >and what I assume Debian-installer bugs. > >Long story short, Debian writes strange/incorrect C/H/S values to the MBR >partition table upon installation, to which testdisk software complains as >"Bad relative sector".
Nothing should be caring about C/H/S at all in the 21st century. Using C/H/S only allows you to access 515MB of disk [1]. *Everything* these days uses LBA instead. What makes you think that the BIOS on this old machine cares about C/H/S? What happens if you tweak the partitioning by hand when installing? >I've tried to install Debian 12 i386 to a 8G disk, using qemu, with guided >automatic partitioning. Testdisk data right after the installation: > >> Disk testz.img - 8589 MB / 8192 MiB - CHS 1045 255 63 >> Current partition structure: >> Partition Start End Size in sectors >> >> 1 P Linux 0 32 33 919 199 48 14774272 >> >> Bad relative sector. >> 2 E extended 919 232 16 1044 52 32 1996802 >> >> Bad relative sector. >> No partition is bootable >> 5 L Linux Swap 919 232 18 1044 52 32 1996800 >> >> Bad relative sector. > > >It seems that testdisk automatically recalculates C/H/S values and shows >corrected data (in the table above). > >Here's what really is present in the MBR (data of the first partition entry): > >> $ ./mbr_my.py testz.img Status: 0x0 >> C/H/S start: 4 4 1 >> Part type: 0x83 >> C/H/S end: 1023 254 2 >> LBA of first sector: 2048 >> Sector count: 14774272 > > >fdisk/cfdisk and parted all create partitions for which testdisk does not >complain. d-i drives parted to make partitions... [1] https://forums.tomshardware.com/threads/lba-chs-bios-prob.685748/ -- Steve McIntyre, Cambridge, UK. st...@einval.com "We're the technical experts. We were hired so that management could ignore our recommendations and tell us how to do our jobs." -- Mike Andrews
