# cryptsetup-resize

## NAME



           cryptsetup-resize - resize an active mapping
    


## SYNOPSIS



           **cryptsetup** _resize_ **[ <options>] <name>**
    


## DESCRIPTION



           Resizes an active mapping <name>.
    
           If --size (in 512-byte sectors) or --device-size is 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
           the LUKS header (see data payload offset in the **luksDump** command).
           For a 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 a volume key for the active device loaded
           in the kernel keyring service, the 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, --volume-key-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 the new size of the device. If unset, the 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 the volume key in the kernel keyring; 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 is 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 the system directory path where cryptsetup searches
               for external token handlers (or token plugins). It must be an
               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 the
               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-description** _text_
               Set the key description in the keyring that will be used for
               passphrase retrieval.
    
           **--key-file** , **-d** _file_
               Read the passphrase from the 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 keyslot is selected for the new key.
    
               The maximum number of keyslots depends on the LUKS version.
               LUKS1 can have up to 8 keyslots. LUKS2 can have up to 32
               keyslots based on keyslot area size and key size, but a valid
               keyslot 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** _seconds_
               The number of seconds to wait before a 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 the token PIN prompt to
               take precedence over the interactive keyslot passphrase
               prompt. If omitted, all available tokens (not protected by
               PIN) will be checked before proceeding further with the
               passphrase prompt.
    
           **--token-only**
               Do not proceed further with the action if the token-based
               keyslot unlock failed. Without the option, the action asks for
               a passphrase to proceed further.
    
               It allows LUKS2 tokens protected by PIN to take precedence
               over the interactive keyslot passphrase prompt.
    
           **--token-type** _type_
               Restrict tokens eligible for operation to a specific token
               _type_. Mostly useful when no --token-id is specified.
    
               It allows LUKS2 _type_ tokens protected by PIN to take
               precedence over the 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.
    
           **--volume-key-keyring** _< key description>_
               Use a volume key stored in a keyring. This allows one to open
               _luks_ and _plain_ device types without giving a passphrase.
    
               For LUKS, the key and associated type have to be readable from
               userspace so that the volume key digest may be verified before
               activation. For devices in reencryption, the option may be
               used twice to specify both old and new volume keys.
    
               For PLAIN type, the user must ensure that the key in the
               keyring is unchanged since activation. Otherwise, reloading
               the key can cause data corruption after an unexpected key
               change.
    
               The _< key description>_ uses keyctl-compatible syntax. This can
               either be a numeric key ID or a string name in the format
               _% <key type>:<key name>_. See also the **KEY IDENTIFIERS** section
               of keyctl(1). When no _% <key type>:_ prefix is specified, we
               assume the key type is _user_ (default type).
    


## CRYPTSETUP



           Part of cryptsetup project
           <https://gitlab.com/cryptsetup/cryptsetup/>. This page is part of
           the _Cryptsetup_ ((open-source disk encryption)) project.
           Information about the project can be found at 
           ⟨https://gitlab.com/cryptsetup/cryptsetup⟩. If you have a bug
           report for this manual page, send it to dm-crypt@saout.de. This
           page was obtained from the project's upstream Git repository
           ⟨https://gitlab.com/cryptsetup/cryptsetup.git⟩ on 2025-08-11. (At
           that time, the date of the most recent commit that was found in
           the repository was 2025-08-01.) If you discover any rendering
           problems in this HTML version of the page, or you believe there is
           a better or more up-to-date source for the page, or you have
           corrections or improvements to the information in this COLOPHON
           (which is _not_ part of the original manual page), send a mail to
           man-pages@man7.org
    
    cryptsetup 2.8.1-git            2025-08-09           _CRYPTSETUP-RESIZE_(8)
    


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