grub2: Invoking grub2-mount
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1 28 Invoking grub2-mount
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1 The program 'grub2-mount' performs a read-only mount of any file system
1 or file system image that GRUB understands, using GRUB's file system
1 drivers via FUSE. (It is only available if FUSE development files were
1 present when GRUB was built.) This has a number of uses:
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1 * It provides a convenient way to check how GRUB will view a file
1 system at boot time. You can use normal command-line tools to
1 compare that view with that of your operating system, making it
1 easy to find bugs.
1
1 * It offers true read-only mounts. Linux does not have these for
1 journalling file systems, because it will always attempt to replay
1 the journal at mount time; while you can temporarily mark the block
1 device read-only to avoid this, that causes the mount to fail.
1 Since GRUB intentionally contains no code for writing to file
1 systems, it can easily provide a guaranteed read-only mount
1 mechanism.
1
1 * It allows you to examine any file system that GRUB understands
1 without needing to load additional modules into your running
1 kernel, which may be useful in constrained environments such as
1 installers.
1
1 * Since it can examine file system images (contained in regular
1 files) just as easily as file systems on block devices, you can use
1 it to inspect any file system image that GRUB understands with only
1 enough privileges to use FUSE, even if nobody has yet written a
1 FUSE module specifically for that file system type.
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1 Using 'grub2-mount' is normally as simple as:
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1 grub-mount /dev/sda1 /mnt
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1 'grub2-mount' must be given one or more images and a mount point as
1 non-option arguments (if it is given more than one image, it will treat
1 them as a RAID set), and also accepts the following options:
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1 '--help'
1 Print a summary of the command-line options and exit.
1
1 '--version'
1 Print the version number of GRUB and exit.
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1 '-C'
1 '--crypto'
1 Mount encrypted devices, prompting for a passphrase if necessary.
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1 '-d STRING'
1 '--debug=STRING'
1 Show debugging output for conditions matching STRING.
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1 '-K prompt|FILE'
1 '--zfs-key=prompt|FILE'
1 Load a ZFS encryption key. If you use 'prompt' as the argument,
1 'grub2-mount' will read a passphrase from the terminal; otherwise,
1 it will read key material from the specified file.
1
1 '-r DEVICE'
1 '--root=DEVICE'
1 Set the GRUB root device to DEVICE. You do not normally need to
1 set this; 'grub2-mount' will automatically set the root device to
1 the root of the supplied file system.
1
1 If DEVICE is just a number, then it will be treated as a partition
1 number within the supplied image. This means that, if you have an
1 image of an entire disk in 'disk.img', then you can use this
1 command to mount its second partition:
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1 grub-mount -r 2 disk.img mount-point
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1 '-v'
1 '--verbose'
1 Print verbose messages.
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