INTEGRITYSETUP(8)
๐ INTEGRITYSETUP(8) ๐ โ the integritysetup girlies' guide
okay so bestie, welcome to the Maintenance Commands section of the manual, and specifically to integritysetup โ the utility for configuring and managing dm-integrity devices. yes this is the whole page. yes it's long. no we are not skipping anything. grab a strawberry ๐ and let's go.
๐ธ NAME ๐ธ
integritysetup โ a whole utility for configuring and managing dm-integrity devices. that's it. that's the name section. slay.
โจ SYNOPSIS โจ
integritysetup <action> [<options>] <action args>
literally that's the shape of it. action, then options, then the action's args. periodt.
๐ฆ DESCRIPTION ๐ฆ
okay so integritysetup is a utility for configuring and managing kernel dm-integrity devices. ๐
the kernel device-mapper dm-integrity target emulates an additional data integrity tag per disk sector and provides transparent data integrity protection of block devices. the way that works is genuinely iconic โ extra tag per sector, no cap.
you can configure these additional integrity tags directly with integritysetup, or indirectly (for authenticated encryption) through LUKS2 and cryptsetup(8). and here's the glow-up moment: unlike dm-verity, dm-integrity devices support both read and write operations. the kernel performs data integrity checking transparently using a selected checksum or cryptographic hash algorithm. ๐คฏ
integrity devices can be activated during boot through integritytab(5), which is part of systemd(1). so boot-time activation is just built in. iconic.
๐ BASIC ACTIONS ๐
integritysetup supports these operations:
๐ FORMAT
format <device>
Formats <device> (calculates space and dm-integrity superblock and wipes the device). like, it wipes it. fully.
<options> can be [--data-device, --batch-mode, --no-wipe, --journal-size, --interleave-sectors, --tag-size, --integrity, --integrity-key-size, --integrity-key-file, --sector-size, --progress-frequency, --progress-json].
๐ OPEN
open <device> <name>
create <name> <device> (OBSOLETE syntax)
Open a mapping with <name> backed by device <device>.
โ ๏ธ if the integrity algorithm of the device is non-default, then the algorithm should be specified with the --integrity option. This will not be detected from the device. so tell it, bestie, it's not psychic.
<options> can be [--data-device, --batch-mode, --journal-watermark, --journal-commit-time, --buffer-sectors, --integrity, --integrity-key-size, --integrity-key-file, --integrity-no-journal, --integrity-recalculate, --integrity-recalculate-reset,--integrity-recovery-mode, --allow-discards, --allow-discards-keyed].
๐ CLOSE
close <name>
remove <name> (OBSOLETE syntax)
Removes existing mapping <name>. bye bestie ๐ซถ
<options> can be [--deferred] or [--cancel-deferred].
๐ STATUS
status <name>
Reports status for the active integrity mapping <name>. the vibe check, basically. ๐
๐ DUMP
dump <device>
Report parameters from the on-disk stored superblock. receipts from the disk itself. ๐
๐ RESIZE
resize <name>
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. After resize, the recalculating flag is set. If --wipe flag is set and the size of the device is increased, the newly added section will be wiped. ๐ง
Increasing the size of integrity volumes has been possible since the Linux kernel version 5.7; shrinking should work on older kernels, too. so growing is the new trick, shrinking is retro-compatible. ๐
<options> can be [--size, --device-size, --wipe].
๐ OPTIONS ๐
this is the big one. every single one. no skipping.
--allow-discardsโ Allow the use of discard (TRIM) requests for the device. This option is available since the Linux kernel version 5.7.--allow-discards-keyedโ Enable secure keyed discard (TRIM) for the device. This option can only be specified if a keyed algorithm (like HMAC) is used. Once keyed discards are enabled, they are always used, even with the--allow-discardoption.
This option is available since Linux kernel version 7.3.
--batch-mode,-qโ Do not ask for confirmation. no "are you sure" pop-ups, we're just going. ๐--bitmap-flush-time msโ Bitmap flush time in milliseconds.
โ ๏ธ WARNING: In case of a crash, it is possible that the data and integrity tag don't match if the journal is disabled. so like. heads up.
--bitmap-sectors-per-bit sectorsโ The number of 512-byte sectors per bitmap bit must be a power of two.--buffer-sectors sectorsโ The number of sectors in one buffer.
The tag area is accessed using buffers; the large buffer size means the I/O size will be larger, but there could be less I/Os issued.
--cancel-deferredโ Removes a previously configured deferred device removal in theclosecommand.--data-device <data_device>โ Specify a separate data device that contains existing data. The<device>will then contain calculated integrity tags and a journal for data on<data_device>.
To not wipe the data device after initial format, also specify --no-wipe option and activate with --integrity-recalculate to recalculate integrity tags automatically.
--debugโ Run in debug mode with full diagnostic logs. Debug output lines are always prefixed by#.--deferredโ Defers device removal in theclosecommand until the last user closes it.--help,-?โ Show help text and default parameters.--integrity,-I algorithmโ Use internal integrity calculation (standalone mode). The integrity algorithm can be CRC (crc32c/crc32), a non-cryptographic hash function (xxhash64) or a hash function (sha1,sha256).
For HMAC (hmac-sha256), you must specify an integrity key and its size. ๐
--integrity-bitmap-mode,-Bโ Use alternate bitmap mode (available since Linux kernel 5.2), wheredm-integrityuses a bitmap instead of a journal. If a bit in the bitmap is 1, the corresponding region's data and integrity tags are not synchronized โ if the machine crashes, the unsynchronized regions will be recalculated. The bitmap mode is faster than the journal mode because we don't have to write the data twice. However, it is also less reliable because if data corruption happens when the machine crashes, it may not be detected. โก fast but spicy.--integrity-inlineโ Store integrity tags in hardware sector integrity fields. The device must support sectors with additional protection information (PI, also known as DIF โ data integrity field) of the requested size. Another storage subsystem must not use the additional field (the device must present a"nop"profile in the kernel). Note that some devices must be reformatted at a low level to support this option; for NVMe devices, seenvme(1)id-nsLBA profiles.
No journal or bitmap is used in this mode. The device should operate with native speed (without any overhead). ๐๏ธ
This option is available since the Linux kernel version 6.11.
--integrity-key-file fileโ The file with the integrity key.--integrity-key-size bytesโ The size of the data integrity key. Maximum is 4096 bytes.--integrity-no-journal,-Dโ Disable the journal for the integrity device.--integrity-recalculateโ Automatically recalculate integrity tags in the kernel on activation. The device can be used during automatic integrity recalculation, but becomes fully integrity protected only after the background operation is finished.
The primary intended use case is to skip initialization (wiping) of the data device after the initial format (see --no-wipe option). This parameter can be used for activation, then the kernel will recalculate integrity tags in the background. The integrity superblock contains a device offset that indicates the boundary to which the integrity tags are already updated. You can check this offset with the dump command. ๐
--integrity-recalculate-resetโ Restart recalculation from the beginning of the device. It can be used to change the integrity checksum function. Note, it does not change the tag length. This option is available since the Linux kernel version 5.13.--integrity-recovery-mode,-Rโ Recovery mode (no journal, no tag checking).--interleave-sectors sectorsโ The number of interleaved sectors.--journal-commit-time msโ Commit time in milliseconds. The journal is written when this time passes (and no explicit flush operation was issued).--journal-crypt algorithmโ Encryption algorithm for the journal data area. You can use a block cipher here, such ascbc-aesor a stream cipher, for example,chacha20orctr-aes.
โ ๏ธ The journal encryption options are only intended for testing. Using journal encryption does not make sense without encryption of the data. so like, don't be weird about it.
--journal-crypt-key-file fileโ The file with the journal encryption key.--journal-crypt-key-size bytesโ The size of the journal encryption key. Maximum is 4096 bytes.--journal-integrity algorithmโ Integrity algorithm for the journal area. See--integrityoption for detailed specification.--journal-integrity-key-file fileโ The file with the integrity key.--journal-integrity-key-size bytesโ The size of the journal integrity key. Maximum is 4096 bytes.--journal-size,-j bytesโ Size of the journal.--journal-watermark percentโ Journal watermark in percent. When the journal size exceeds this watermark, the journal flush will be started. ๐ง--no-wipeโ Do not wipe the device after formatting. A device that is not initially wiped will contain invalid checksums. so like, you asked for it.--progress-frequency secondsโ Print a separate line every<seconds>with wipe progress.--progress-jsonโ Prints wipe progress data in JSON format, which is suitable mostly for machine processing. It prints a separate line every half second (or based on--progress-frequencyvalue). The JSON output looks as follows during wipe progress (except it's a compact single line):
{
"device":"/dev/sda", // backing device or file
"device_bytes":"8192", // bytes wiped so far
"device_size":"44040192", // total bytes to wipe
"speed":"126877696", // calculated speed in bytes per second (based on progress so far)
"eta_ms":"2520012", // estimated time to finish wipe in milliseconds
"time_ms":"5561235" // total time spent wiping device in milliseconds
}
๐ Note on numbers in JSON output: Due to JSON parsers' limitations, all numbers are represented in a string format due to the need for full 64-bit unsigned integers. yes, strings. it's giving "64-bit problems". ๐ญ
--sector-size,-s bytesโ Sector size (power of two:512,1024,2048,4096).--tag-size,-t bytesโ Size of the integrity tag per-sector (here, the integrity function will store the authentication tag).
The size can be smaller than the output size of the hash function; in that case, only part of the hash will be stored.
--usageโ Show short option help.--verbose,-vโ Print more information on command execution.--version,-Vโ Show the program version.--wipeโ Wipe the newly allocated area after resizing to a bigger size. If this flag is not set, checksums will be calculated for previously stored data in the newly allocated area. ๐งผ
๐จ LEGACY COMPATIBILITY OPTIONS ๐จ
ok bestie listen. Do not use these options until you need compatibility with a specific old kernel. Like, genuinely. They're here for the old-kernel girlies and nobody else. ๐
--integrity-legacy-paddingโ uses the inefficient legacy padding. it's giving โจinefficientโจ for a reason, don't @ me.--integrity-legacy-hmacโ uses the old flawed HMAC calculation. and spoiler alert: it also does not protect the superblock. ๐--integrity-legacy-recalculateโ allows insecure recalculating of volumes with HMAC keys. the tea here is that the recalculation offset in the superblock is not protected. be so careful bestie.
๐ RETURN CODES ๐
integritysetup returns 0 on success and a non-zero value on error. periodt.
The error codes are, no cap:
1โ wrong parameters ๐2โ no permission ๐3โ out of memory ๐ญ4โ wrong device specified ๐ซ5โ device already exists or device is busy ๐ค
๐ NOTES ๐
Formatting and activating an integrity device always require superuser privilege, because the superblock gets calculated and handled in the dm-integrity kernel target. so yeah, you're gonna need the big-girl permissions for this one. ๐
โจ EXAMPLES โจ
Format the device with default standalone mode (CRC32C):
integritysetup format <device>
Open the device with default parameters:
integritysetup open <device> test
Format the device in standalone mode for use with HMAC(SHA256):
integritysetup format <device> --tag-size 32 --integrity hmac-sha256
--integrity-key-file <keyfile> --integrity-key-size <key_bytes>
Open (activate) the device with HMAC(SHA256) and HMAC key in file:
integritysetup open <device> test --integrity hmac-sha256
--integrity-key-file <keyfile> --integrity-key-size <key_bytes>
Dump dm-integrity superblock information:
integritysetup dump <device>
๐ฆ DM-INTEGRITY ON-DISK FORMAT ๐ฆ
The on-disk format specification is available on the DMIntegrity <https://gitlab.com/cryptsetup/cryptsetup/wikis/DMIntegrity> page. go read it, it's the lore. ๐
๐ AUTHORS ๐
The integritysetup tool is written by Milan Broz <gmazyland@gmail.com>. absolute main character energy, we stan. ๐
๐ REPORTING BUGS ๐
Report bugs at the cryptsetup mailing list <cryptsetup@lists.linux.dev> or in the Issues project section <https://gitlab.com/cryptsetup/cryptsetup/-/issues/new>.
Please attach the output of the failed command with the --debug option added. fr fr, without the debug output we're just out here guessing and that's not the vibe. ๐
๐ธ SEE ALSO ๐ธ
- Cryptsetup FAQ <https://gitlab.com/cryptsetup/cryptsetup/wikis/FrequentlyAskedQuestions>
cryptsetup(8),integritysetup(8)andveritysetup(8)
๐ CRYPTSETUP ๐
Part of the cryptsetup project <https://gitlab.com/cryptsetup/cryptsetup/>. it's a whole family, iykyk. ๐ซถ
ok that's the whole page bestie, you're officially an integritysetup girlie now ๐
this was integritysetup 2.8.8, dated 2026-09-07, from the INTEGRITYSETUP(8) section โ go format something responsibly, mwah ๐โจ๐
๐ฆ where this page comes from
- arch rolling: cryptsetup 2.8.8-1 ยท GPL-2.0-or-later
- fedora 44: integritysetup 2.8.8-1.fc44 ยท GPL-2.0-or-later WITH cryptsetup-OpenSSL-exception AND LGPL-2.1-or-later WITH cryptsetup-OpenSSL-exception
- nixpkgs unstable: cryptsetup 2.8.8
- ๐ girlified by deepseek-ai/DeepSeek-V4.1-Flash on : a language model's rewrite of the original, under its terms