e2undo(8) - man - phpman

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⚡ TLDR: e2undo (tldr-pages)

Replay undo logs for an ext2/ext3/ext4 filesystem.

Display information about a specific undo file
e2undo -h {{path/to/undo_file}} {{/dev/sdXN}}
Perform a dry-run and display the candidate blocks for replaying
e2undo -nv {{path/to/undo_file}} {{/dev/sdXN}}
Perform an undo operation
e2undo {{path/to/undo_file}} {{/dev/sdXN}}
Perform an undo operation and display verbose information
e2undo -v {{path/to/undo_file}} {{/dev/sdXN}}
Write the old contents of the block to an undo file before overwriting a filesystem block
e2undo -z {{path/to/file.e2undo}} {{path/to/undo_file}} {{/dev/sdXN}}

E2UNDO(8) System Manager's Manual E2UNDO(8)

NAME
e2undo - Replay an undo log for an ext2/ext3/ext4 file system

SYNOPSIS
e2undo [ -f ] [ -h ] [ -n ] [ -o offset ] [ -v ] [ -z undo_file ] undo_log device

DESCRIPTION
e2undo will replay the undo log undo_log for an ext2/ext3/ext4 file system found on device.
This can be used to undo a failed operation by an e2fsprogs program.

OPTIONS
-f Normally, e2undo will check the file system superblock to make sure the undo log
matches with the file system on the device. If they do not match, e2undo will refuse
to apply the undo log as a safety mechanism. The -f option disables this safety mech‐
anism.

-h Display a usage message.

-n Dry-run; do not actually write blocks back to the file system.

-o offset
Specify the file system's offset (in bytes) from the beginning of the device or file.

-v Report which block we're currently replaying.

-z undo_file
Before overwriting a file system block, write the old contents of the block to an undo
file. This undo file can be used with e2undo(8) to restore the old contents of the
file system should something go wrong. If the empty string is passed as the undo_file
argument, the undo file will be written to a file named e2undo-device.e2undo in the
directory specified via the E2FSPROGS_UNDO_DIR environment variable.

WARNING: The undo file cannot be used to recover from a power or system crash.

AUTHOR
e2undo was written by Aneesh Kumar K.V. (aneesh.kumar AT linux.com)

AVAILABILITY
e2undo is part of the e2fsprogs package and is available from http://e2fsprogs.source‐
forge.net.