man 8 cryptsetup-resize

CRYPTSETUP-RESIZE(8)         Maintenance Commands         CRYPTSETUP-RESIZE(8)

NAME
       cryptsetup-resize - resize an active mapping

SYNOPSIS
       cryptsetup resize [<options>] <name> 

DESCRIPTION
       Resizes an active mapping <name>.

       If --size (in 512-bytes sectors) or --device-size are not specified,
       the size is computed from the underlying device. For LUKS it is the
       size of the underlying device without the area reserved for LUKS header
       (see data payload offset in luksDump command). For plain crypt device,
       the whole device size is used.

       Note that this does not change the raw device geometry, it just changes
       how many sectors of the raw device are represented in the mapped
       device.

       If cryptsetup detected volume key for active device loaded in kernel
       keyring service, resize action would first try to retrieve the key
       using a token. Only if it failed, it'd ask for a passphrase to unlock a
       keyslot (LUKS) or to derive a volume key again (plain mode). The kernel
       keyring is used by default for LUKS2 devices.

       <options> can be [--size, --device-size, --token-id, --token-only,
       --token-type, --key-slot, --key-file, --keyfile-size, --keyfile-offset,
       --timeout, --disable-external-tokens, --disable-locks,
       --disable-keyring, --verify-passphrase, --timeout,
       --external-tokens-path].

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.

       --device-size size[units]
           Sets new size of the device. If unset real device size is used.

           If no unit suffix is specified, the size is in bytes.

           Unit suffix can be S for 512 byte sectors, K/M/G/T (or
           KiB,MiB,GiB,TiB) for units with 1024 base or KB/MB/GB/TB for 1000
           base (SI scale).

       --disable-external-tokens
           Disable loading of plugins for external LUKS2 tokens.

       --disable-keyring
           Do not load volume key in kernel keyring and store it directly in
           the dm-crypt target instead. This option is supported only for the
           LUKS2 type.

       --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).

       --external-tokens-path absolute_path
           Override system directory path where cryptsetup searches for
           external token handlers (or token plugins). It must be absolute
           path (starting with '/' character).

       --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.

       --size, -b <number of 512 byte sectors> 
           Set the size of the device in sectors of 512 bytes.

       --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.

       --token-id
           Specify what token to use and allow token PIN prompt to take
           precedence over interactive keyslot passphrase prompt. If omitted,
           all available tokens (not protected by PIN) will be checked before
           proceeding further with passphrase prompt.

       --token-only
           Do not proceed further with action if token based keyslot unlock
           failed. Without the option, action asks for passphrase to proceed
           further.

           It allows LUKS2 tokens protected by PIN to take precedence over
           interactive keyslot passphrase prompt.

       --token-type type
           Restrict tokens eligible for operation to specific token type.
           Mostly useful when no --token-id is specified.

           It allows LUKS2 type tokens protected by PIN to take precedence
           over interactive keyslot passphrase prompt.

       --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-RESIZE(8)