cryptsetup-fvault2Dump - dump the header information of a FVAULT2 (FileVault2 compatible) device

       Part of cryptsetupproject <https://gitlab.com/cryptsetup/cryptsetup/>.

cryptsetup 2.8.0                                   2025-07-25                          CRYPTSETUP-FVAULT2DUMP(8)

       Dump the header information of a FVAULT2 (FileVault2 compatible) device.

       If the --dump-volume-key option is used, the FVAULT2 device volume key is dumped instead of header
       information. You have to provide password or keyfile to dump volume key.

       Beware that the volume key can be used to decrypt the data stored in the container without a passphrase.
       This means that if the volume key is compromised, the whole device has to be erased to prevent further
       access. Use this option carefully.

       <options> can be [--dump-volume-key, --volume-key-file, --key-file, --keyfile-offset, --keyfile-size,
       --timeout].

       cryptsetup-fvault2Dump - dump the header information of a FVAULT2 (FileVault2 compatible) device

--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.

       --debugor--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.

       --dump-volume-key,--dump-master-key(OBSOLETEalias)
           Print the volume key in the displayed information. Use with care, as the volume key can be used to
           bypass the passphrases, see also option --volume-key-file.

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

       --key-file,-dname
           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 NOTESONPASSPHRASEPROCESSING in cryptsetup(8) for more information.

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

       --keyfile-size,-lvalue
           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.

       --timeout,-t<numberofseconds>
           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.

       --usage
           Show short option help.

       --version,-V
           Show the program version.

       --volume-key-file,--master-key-file(OBSOLETEalias)
           Use a volume key stored in a file. The volume key is stored in a file instead of being printed out to
           standard output.

       Report bugs at cryptsetupmailinglist <cryptsetup@lists.linux.dev> or in Issuesprojectsection
       <https://gitlab.com/cryptsetup/cryptsetup/-/issues/new>.

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

CryptsetupFAQ <https://gitlab.com/cryptsetup/cryptsetup/wikis/FrequentlyAskedQuestions>

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

cryptsetupfvault2Dump[<options>]<device>