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Hostblogger · DebianCurated

Repairing a Debian system that no longer boots after upgrades

Summary

Manuel Schmitt documents a rescue procedure for a Debian system whose upgrade left the kernel package, GRUB configuration and mdadm configuration inconsistent. The affected system had been upgraded from Debian Lenny to Squeeze. /boot contained a bzImage, but not the vmlinuz that GRUB detection expected.

Ideas

  • An empty grub.cfg can result when no suitable linux-image is installed.
  • A rescue system with bind mounts allows package and bootloader repairs in a chroot.
  • mdadm --examine --scan can reconstruct a lost RAID configuration from existing metadata.

Insights

  • Regular package updates do not guarantee a complete boot path across several distribution upgrades.
  • Bootability has to be tested explicitly after kernel and RAID changes.

Facts

  • The repair reinstalled a linux-image package in the chroot.

Recommendations

  • Before a distribution upgrade, check the kernel package, /boot usage and RAID state.
  • Keep a tested rescue system and a documented chroot procedure ready.

References

Read the original article on Hostblogger

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