table of contents
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-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
If the --verify-passphrase option is not specified, this option also switches off the passphrase verification.
--debug or --debug-json
If --debug-json is used, additional LUKS2 JSON data structures are printed.
--device-size size[units]
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-keyring
--disable-locks
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>
--header <device or file storing the LUKS header>
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, -?
--key-description text
--key-file, -d 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
--keyfile-size, -l value
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>
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>
--timeout, -t seconds
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
--token-only
It allows LUKS2 tokens protected by PIN to take precedence over the interactive keyslot passphrase prompt.
--token-type type
It allows LUKS2 type tokens protected by PIN to take precedence over the interactive keyslot passphrase prompt.
--usage
--verify-passphrase, -y
--version, -V
--volume-key-keyring <key description>
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).
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 the output of the failed command with --debug option added.
SEE ALSO¶
Cryptsetup FAQ <https://gitlab.com/cryptsetup/cryptsetup/wikis/FrequentlyAskedQuestions>
CRYPTSETUP¶
Part of cryptsetup project <https://gitlab.com/cryptsetup/cryptsetup/>.
2025-08-19 | cryptsetup 2.8.1 |