Answer Posted / amsin21

Need to know the grub error code for suggesting the resolutions.

Errors Reported by the Stage 1
------------------------------
The general way that the Stage 1 handles errors is to print
an error string and then halt. Pressing Ctrl-Alt-Del will
reboot.

The following is a comprehensive list of error messages for
the Stage 1:

* "Hard Disk Error"

This error message will occur if the Stage 2 or Stage 1.5 is
being read from a hard disk, and the attempt to determine
the size and geometry of the hard disk fails.

* "Floppy Error"

This error message will occur if the Stage 2 or Stage 1.5 is
being read from a floppy disk, and the attempt to determine
the size and geometry of the floppy disk fails. It's listed
as a different error since the probe sequence is different
than for hard disks.

* "Read Error"

This error message will occur if a disk read error happens
while trying to read the Stage 2 or Stage 1.5.

* "Geom Error"

This error message will occur if the location of the Stage 2
or Stage 1.5 is not in the area supported by reading the
disk with the BIOS directly. This could occur because the
BIOS translated geometry has been changed by the user or the
disk is moved to another machine or controller after
installation, or GRUB was not installed using itself (if it
was, the Stage 2 version of this error would have been seen
during that process and it would not have completed the
install).

Errors Reported by the Stage 1.5
--------------------------------

The general way that the Stage 1.5 handles errors is to
print an error number in the form "Error: " and then halt.
Pressing Ctrl-Alt-Del will reboot.

The error numbers correspond to the Errors Reported by the
Stage 2 in the listed sequence.

Errors Reported by the Stage 2
------------------------------

The general way that the Stage 2 handles errors is to abort
the operation in question, print an error string, then (if
possible) either continue based on the fact that an error
occurred or wait for the user to deal with the error.

The following is a comprehensive list of error messages for
the Stage 2 (error numbers for the Stage 1.5 are listed
before the colon in each description):

1) "Selected item won't fit into memory"

This error is returned if a kernel, module, or raw file load
command is either trying to load it's data such that it
won't fit into memory or it is simply too big.

2) "Selected disk doesn't exist"

This error is returned if the device part of a device- or
full filename refers to a disk or BIOS device that is not
present or not recognized by the BIOS in the system.

3) "Disk read error"

This error is returned if there is a disk read error when
trying to probe or read data from a particular disk.

4) "Disk write error"

This error is returned if there is a disk write error when
trying to write to a particular disk. This would generally
only occur during an install of set active partition command.

5) "Disk geometry error"

This error is returned when a read is attempted at a linear
block address beyond the end of the BIOS translated area.
This generally happens if your disk is larger than the BIOS
can handle (512MB for (E)IDE disks on older machines or
larger than 8GB in general).

6) "Attempt to access block outside partition"

This error is returned if a linear block address is outside
of the disk partition. This generally happens because of a
corrupt filesystem on the disk or a bug in the code handling
it in GRUB (it's a great debugging tool).

7) "Partition table invalid or corrupt"

This error is returned if the sanity checks on the integrity
of the partition table fail. This is a bad sign.

8) "No such partition"

This error is returned if a partition is requested in the
device part of a device- or full filename which isn't on the
selected disk.

9) "Bad filename (must be absolute pathname or blocklist)"

This error is returned if a filename is requested which
doesn't fit the syntax/rules listed in the Filesystem
Description.

10) "Bad file or directory type"

This error is returned if a file requested is not a regular
file, but something like a symbolic link, directory, or FIFO.

11) "File not found"

This error is returned if the specified filename cannot be
found, but everything else (like the disk/partition info) is OK.

12) "Cannot mount selected partition"

This error is returned if the partition requested exists,
but the filesystem type cannot be recognized by GRUB.

13) "Inconsistent filesystem structure"

This error is returned by the filesystem code to denote an
internal error caused by the sanity checks of the filesystem
structure on disk not matching what it expects. This is
usually caused by a corrupt filesystem or bugs in the code
handling it in GRUB.

14) "Filesystem compatibility error, can\'t read whole file"

Some of the filesystem reading code in GRUB has limits on
the length of the files it can read. This error is returned
when the user runs into such a limit.

15) "Error while parsing number"

This error is returned if GRUB was expecting to read a
number and encountered bad data.

16) "Device string unrecognizable"

This error is returned if a device string was expected, and
the string encountered didn't fit the syntax/rules listed in
the Filesystem Description.

17) "Invalid device requested"

This error is returned if a device string is recognizable
but does not fall under the other device errors.

18) "Invalid or unsupported executable format"

This error is returned if the kernel image boing loaded is
not recognized as Multiboot or one of the supported native
formats (Linux zImage or bzImage, FreeBSD, or NetBSD).

19) "Loading below 1MB is not supported"

This error is returned if the lowest address in a kernel is
below the 1MB boundary. The Linux zImage format is a special
case and can be handled since it has a fixed loading address
and maximum size.

20) "Unsupported Multiboot features requested"

This error is returned when the Multiboot features word in
the Multiboot header requires a feature that is not
recognized. The point of this is that the kernel requires
special handling which GRUB is likely unable to provide.

21) "Unknown boot failure"

This error is returned if the boot attempt did not succeed
for reasons which are unknown.

22) "Must load Multiboot kernel before modules"

This error is returned if the module load command is used
before loading a Multiboot kernel. It only makes sense in
this case anyway, as GRUB has no idea how to communicate the
presence of location of such modules to a
non-Multiboot-aware kernel.

23) "Must load Linux kernel before initrd"

This error is returned if the initrd command is used before
loading a Linux kernel. Similar to the above error, it only
makes sense in that case anyway.

24) "Cannot boot without kernel loaded"

This error is returned if GRUB is told to execute the boot
sequence without having a kernel to start.

25) "Unrecognized command"

This error is returned if an unrecognized command is entered
into the command-line or in a boot sequence section of a
config file and that entry is selected.

26) "Bad or incompatible header on compressed file"

This error is returned if the file header for a supposedly
compressed file is bad.

27) "Bad or corrupt data while decompressing file"

This error is returned the run-length decompression code
gets an internal error. This is usually from a corrupt file.

28) "Bad or corrupt version of stage1/stage2"

This error is returned if the install command is pointed to
incompatible or corrupt versions of the stage1 or stage2. It
can't detect corruption in general, but this is a sanity
check on the version numbers, which should be correct.

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