recover from boot failure initramfs
HI guys,
Can anyone shed some light on this article? https://access.redhat.com/solutions/365693
i have a test system that will not get past the initramfs stage at boot after a kernel update and the first command in the article "chroot /mnt/sysimage" fails because a linux filesysystem was not found by the rescue disc before that.
Due to that I am not able to run the dracut command to recreate the initramfs which I hope would resolve the boot error.
Responses
Usually rescue mode's typically pretty good about finding valid linux filesystem structures (partitions, logical volumes, meta-devices, filesystems).Typically a couple reasons for not finding a filesystem:
- the filesystem is corrupted
- the device vtoc is corrupted
- if using LVM/MD structures to host filesystems, the LVM/MD structures are corrupted
First thing you'll probably want to do, after you boot to rescue-mode, is check to see if the disk has a valid partition-table. Depending on disk partitioning-scheme (MBR vs GPT), you can use tools like fdisk, sfdisk, parted or even lsblk to see what partitions are available. Assuming one of those tools confirms that the partition-table is still valid, you can try manually-mounting the filesystems or onlinlining any LVM/MD volumes you find (and see what types of errors those efforts produce).
Beyond the above general-response, we'd probably need more diagnostic information to go from.
As Tom said, if rescue mode can't find linux file system details then could probably a corrupt file system layout (partition details). So, check in rescue mode if you could mount and access files on those partitions. I'm sure this would fail, since file system meta-data may be corrupt. If you are unable to mount and access file systems then need to re-create it file system layout which is at technical risk if not executed properly. Again, if file system was created on top of lvms then this structure also needs to be re-created as it was before. This is possible only if u know earlier lvm layout.
Welcome! Check out the Getting Started with Red Hat page for quick tours and guides for common tasks.
