'\" t
.\"     Title: cryptsetup-resize
.\"    Author: [see the "AUTHOR(S)" section]
.\" Generator: Asciidoctor 2.0.12
.\"      Date: 2025-06-04
.\"    Manual: Maintenance Commands
.\"    Source: cryptsetup 2.7.2
.\"  Language: English
.\"
.TH "CRYPTSETUP\-RESIZE" "8" "2025-06-04" "cryptsetup 2.7.2" "Maintenance Commands"
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.SH "NAME"
cryptsetup\-resize \- resize an active mapping
.SH "SYNOPSIS"
.sp
\fBcryptsetup \fIresize\fP [<options>] <name>\fP
.SH "DESCRIPTION"
.sp
Resizes an active mapping <name>.
.sp
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 \fBluksDump\fP command). For plain crypt device, the
whole device size is used.
.sp
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.
.sp
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\(cqd 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.
.sp
\fB<options>\fP 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].
.SH "OPTIONS"
.sp
\fB\-\-batch\-mode, \-q\fP
.RS 4
Suppresses all confirmation questions. Use with care!
.sp
If the \-\-verify\-passphrase option is not specified, this option also
switches off the passphrase verification.
.RE
.sp
\fB\-\-debug or \-\-debug\-json\fP
.RS 4
Run in debug mode with full diagnostic logs. Debug output lines are
always prefixed by \fB#\fP.
.sp
If \-\-debug\-json is used, additional LUKS2 JSON data structures are printed.
.RE
.sp
\fB\-\-device\-size\fP \fIsize[units]\fP
.RS 4
Sets new size of the device. If unset real device size is used.
.sp
If no unit suffix is specified, the size is in bytes.
.sp
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).
.RE
.sp
\fB\-\-disable\-external\-tokens\fP
.RS 4
Disable loading of plugins for external LUKS2 tokens.
.RE
.sp
\fB\-\-disable\-keyring\fP
.RS 4
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.
.RE
.sp
\fB\-\-disable\-locks\fP
.RS 4
Disable lock protection for metadata on disk. This option is valid
only for LUKS2 and ignored for other formats.
.sp
\fBWARNING:\fP 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).
.RE
.sp
\fB\-\-external\-tokens\-path\fP \fIabsolute_path\fP
.RS 4
Override system directory path where cryptsetup searches for external token
handlers (or token plugins). It must be absolute path (starting with \(aq/\(aq character).
.RE
.sp
\fB\-\-header <device or file storing the LUKS header>\fP
.RS 4
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.
.sp
For commands that change the LUKS header (e.g. \fIluksAddKey\fP),
specify the device or file with the LUKS header directly as the LUKS
device.
.RE
.sp
\fB\-\-help, \-?\fP
.RS 4
Show help text and default parameters.
.RE
.sp
\fB\-\-key\-file, \-d\fP \fIname\fP
.RS 4
Read the passphrase from file.
.sp
If the name given is "\-", then the passphrase will be read from stdin.
In this case, reading will not stop at newline characters.
.sp
See section \fINOTES ON PASSPHRASE PROCESSING\fP in \fBcryptsetup\fP(8) for more information.
.RE
.sp
\fB\-\-keyfile\-offset\fP \fIvalue\fP
.RS 4
Skip \fIvalue\fP bytes at the beginning of the key file.
.RE
.sp
\fB\-\-keyfile\-size, \-l\fP \fIvalue\fP
.RS 4
Read a maximum of \fIvalue\fP 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.
.sp
This option is useful to cut trailing newlines, for example. If
\-\-keyfile\-offset is also given, the size count starts after the offset.
.RE
.sp
\fB\-\-key\-slot, \-S <0\-N>\fP
.RS 4
For LUKS operations that add key material, this option allows you to
specify which key slot is selected for the new key.
.sp
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.
.RE
.sp
\fB\-\-size, \-b <number of 512 byte sectors>\fP
.RS 4
Set the size of the device in sectors of 512 bytes.
.RE
.sp
\fB\-\-timeout, \-t <number of seconds>\fP
.RS 4
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.
.sp
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.
.RE
.sp
\fB\-\-token\-id\fP
.RS 4
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.
.RE
.sp
\fB\-\-token\-only\fP
.RS 4
Do not proceed further with action if token based keyslot unlock failed. Without the
option, action asks for passphrase to proceed further.
.sp
It allows LUKS2 tokens protected by PIN to take precedence over interactive keyslot
passphrase prompt.
.RE
.sp
\fB\-\-token\-type\fP \fItype\fP
.RS 4
Restrict tokens eligible for operation to specific token \fItype\fP.
Mostly useful when no \-\-token\-id is specified.
.sp
It allows LUKS2 \fItype\fP tokens protected by PIN to take precedence over interactive keyslot
passphrase prompt.
.RE
.sp
\fB\-\-usage\fP
.RS 4
Show short option help.
.RE
.sp
\fB\-\-verify\-passphrase, \-y\fP
.RS 4
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.
.RE
.sp
\fB\-\-version, \-V\fP
.RS 4
Show the program version.
.RE
.SH "REPORTING BUGS"
.sp
Report bugs at \c
.MTO "cryptsetup\(atlists.linux.dev" "\fBcryptsetup mailing list\fP"
or in \c
.URL "https://gitlab.com/cryptsetup/cryptsetup/\-/issues/new" "\fBIssues project section\fP" "."
.sp
Please attach output of the failed command with \-\-debug option added.
.SH "SEE ALSO"
.sp
.URL "https://gitlab.com/cryptsetup/cryptsetup/wikis/FrequentlyAskedQuestions" "\fBCryptsetup FAQ\fP" ""
.sp
\fBcryptsetup\fP(8), \fBintegritysetup\fP(8) and \fBveritysetup\fP(8)
.SH "CRYPTSETUP"
.sp
Part of \c
.URL "https://gitlab.com/cryptsetup/cryptsetup/" "\fBcryptsetup project\fP" "."