Package: grub-pc Version: 2.12-5 Severity: grave Hello. Since version 2.06-8, when #1021846 has been fixed, GRUB may randomly break and fail to boot. When GRUB is broken, it no more boot, reboot don't help.
"error: unknown filesystem" "GRUB rescue:" The frequency of breakdowns is various. May be 10 normal boots, 1 fail. 3 normal boot, 1 fail. I found, that one thing may cause failure in next boot with high probability: delete logs $ cd /var/log $ sudo rm syslog daemon.log messages debug $ sudo reboot To fix the GRUB I boot from LiveCD and simply type in console: # mount /dev/sda1 /mnt # umount /mnt # reboot I also used fsck.f2fs, but it usually don't find errors. $ sudo fdisk --list-details Disk /dev/sda: 29.82 GiB, 32017047552 bytes, 62533296 sectors Disk model: TS32GSSD370S Units: sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disklabel type: dos Disk identifier: 0xc7177f7e Device Boot Start End Sectors Id Type Start-C/H/S End-C/H/S Attrs /dev/sda1 2048 22763519 22761472 83 Linux 4/4/1 1023/254/2 /dev/sda2 * 29679616 62531583 32851968 7 HPFS/NTFS/exFAT 1023/254/2 1023/254/2 80 $ disktype /dev/sda1 --- /dev/sda1 Block device, size 10.85 GiB (11653873664 bytes) F2FS file system (version 1.14)
