man 8 cryptsetup-repair

CRYPTSETUP-REPAIR(8)         Maintenance Commands         CRYPTSETUP-REPAIR(8)

NAME
       cryptsetup-repair - repair the device metadata

SYNOPSIS
       cryptsetup repair [<options>] <device> 

DESCRIPTION
       Tries to repair the device metadata if possible. Currently supported
       only for LUKS device type.

       This command is useful to fix some known benign LUKS metadata header
       corruptions. Only basic corruptions of unused keyslot are fixable. This
       command will only change the LUKS header, not any key-slot data. You
       may enforce LUKS version by adding --type option.

       It also repairs (upgrades) LUKS2 reencryption metadata by adding a
       metadata digest that protects it against malicious changes.

       If LUKS2 reencryption was interrupted in the middle of writing
       reencryption segment the repair command can be used to perform
       reencryption recovery so that reencryption can continue later.
       Repairing reencryption requires verification of reencryption keyslot so
       passphrase or keyfile is needed.

       <options> can be [--timeout, --verify-passphrase, --disable-locks,
       --type, --header, --key-file, --keyfile-size, --keyfile-offset,
       --key-slot].

       WARNING: Always create a binary backup of the original header before
       calling this command.

OPTIONS
       --batch-mode, -q
           Suppresses all confirmation questions. Use with care!

           If the --verify-passphrase option is not specified, this option
           also switches off the passphrase verification.

       --debug or --debug-json
           Run in debug mode with full diagnostic logs. Debug output lines are
           always prefixed by #.

           If --debug-json is used, additional LUKS2 JSON data structures are
           printed.

       --disable-locks
           Disable lock protection for metadata on disk. This option is valid
           only for LUKS2 and ignored for other formats.

           WARNING: Do not use this option unless you run cryptsetup in a
           restricted environment where locking is impossible to perform
           (where /run directory cannot be used).

       --header <device or file storing the LUKS header> 
           Use a detached (separated) metadata device or file where the LUKS
           header is stored. This option allows one to store ciphertext and
           LUKS header on different devices.

           For commands that change the LUKS header (e.g. luksAddKey), specify
           the device or file with the LUKS header directly as the LUKS
           device.

       --help, -?
           Show help text and default parameters.

       --key-file, -d name
           Read the passphrase from file.

           If the name given is "-", then the passphrase will be read from
           stdin. In this case, reading will not stop at newline characters.

           See section NOTES ON PASSPHRASE PROCESSING in cryptsetup(8) for
           more information.

       --keyfile-offset value
           Skip value bytes at the beginning of the key file.

       --keyfile-size, -l value
           Read a maximum of value bytes from the key file. The default is to
           read the whole file up to the compiled-in maximum that can be
           queried with --help. Supplying more data than the compiled-in
           maximum aborts the operation.

           This option is useful to cut trailing newlines, for example. If
           --keyfile-offset is also given, the size count starts after the
           offset.

       --key-slot, -S <0-N> 
           For LUKS operations that add key material, this option allows you
           to specify which key slot is selected for the new key.

           The maximum number of key slots depends on the LUKS version. LUKS1
           can have up to 8 key slots. LUKS2 can have up to 32 key slots based
           on key slot area size and key size, but a valid key slot ID can
           always be between 0 and 31 for LUKS2.

       --timeout, -t <number of seconds> 
           The number of seconds to wait before timeout on passphrase input
           via terminal. It is relevant every time a passphrase is asked. It
           has no effect if used in conjunction with --key-file.

           This option is useful when the system should not stall if the user
           does not input a passphrase, e.g. during boot. The default is a
           value of 0 seconds, which means to wait forever.

       --type <device-type> 
           Specifies required device type, for more info read BASIC ACTIONS
           section in cryptsetup(8).

       --usage
           Show short option help.

       --verify-passphrase, -y
           When interactively asking for a passphrase, ask for it twice and
           complain if both inputs do not match. Ignored on input from file or
           stdin.

       --version, -V
           Show the program version.

REPORTING BUGS
       Report bugs at cryptsetup mailing list <cryptsetup@lists.linux.dev> or
       in Issues project section
       <https://gitlab.com/cryptsetup/cryptsetup/-/issues/new>.

       Please attach output of the failed command with --debug option added.

SEE ALSO
       Cryptsetup FAQ
       <https://gitlab.com/cryptsetup/cryptsetup/wikis/FrequentlyAskedQuestions> 

       cryptsetup(8), integritysetup(8) and veritysetup(8)

CRYPTSETUP
       Part of cryptsetup project <https://gitlab.com/cryptsetup/cryptsetup/>.

cryptsetup 2.7.2                  2025-06-13              CRYPTSETUP-REPAIR(8)