DMSETUP(8) MAINTENANCE COMMANDS DMSETUP(8) (NAME) dmsetup - (Device-Mapper) (SYNOPSIS) dmsetup clear device_name dmsetup create device_name [-n|--notable|--table table|table_file] [--readahead [+]sectors|auto|none] [-u|--uuid uuid] [--addnodeoncreate|--addnodeonresume] dmsetup create --concise [concise_device_specification] dmsetup deps [-o options] [device_name ...] dmsetup help [-c|-C|--columns] dmsetup info [device_name ...] dmsetup info -c|-C|--columns [--count count] [--interval seconds] [--noheadings|--headings none|abbrev|full|0|1|2] [-o fields] [-O|--sort sort_fields] [--nameprefixes] [--separator separator] [device_name] dmsetup load device_name [--table table|table_file] dmsetup ls [--target target_type] [-o options] [--exec command] [--tree] dmsetup mangle [device_name ...] dmsetup measure [device_name ...] dmsetup message device_name sector message dmsetup mknodes [device_name ...] dmsetup reload device_name [--table table|table_file] dmsetup remove [-f|--force] [--retry] [--deferred] device_name ... dmsetup remove_all [-f|--force] [--deferred] dmsetup rename device_name new_name dmsetup rename device_name --setuuid uuid dmsetup resume device_name ... [--addnodeoncreate|--addnodeonresume] [--noflush] [--nolockfs] [--readahead [+]sectors|auto|none] dmsetup setgeometry device_name cyl head sect start dmsetup splitname device_name [subsystem] dmsetup stats command [options] dmsetup status [--target target_type] [--noflush] [device_name ...] dmsetup suspend device_name ... [--nolockfs] [--noflush] dmsetup table [--concise] [--target target_type] [--showkeys] [device_name ...] dmsetup targets dmsetup udevcomplete cookie dmsetup udevcomplete_all [age_in_minutes] dmsetup udevcookie dmsetup udevcreatecookie dmsetup udevflags cookie dmsetup udevreleasecookie [cookie] dmsetup version dmsetup wait device_name [--noflush] [event_nr] dmsetup wipe_table device_name ... [-f|--force] [--noflush] [--nolockfs] devmap_name major minor devmap_name major:minor (DESCRIPTION) dmsetup (device-mapper) . ( ) (target) . dmsetup . uuid . dmsetup devmap_name ( ) : dmsetup info -c --noheadings -j major -m minor. (OPTIONS) --addnodeoncreate /dev/mapper dmsetup create. --addnodeonresume /dev/mapper dmsetup resume ( udev). --checks . . . -c|-C|--columns <>. --count count . . . -f|--force (). -h|--help ( ) ( help). --inactive (live) . 4.16.0 . --interval seconds . --interval --count . . --manglename auto|hex|none UUID (whitelist) mangling_mode (mangle) . UUID (unmangled) : auto ( ) hex ( ) none ( ). auto . : 0-9, A-Z, a-z, #+-.:=@_. udev . ( ) \x . DM_DEFAULT_NAME_MANGLING_MODE . -j| --major major (major) . -m|--minor minor (minor) . -n|--notable . --nameprefixes "DM_" . --noheadings field=value ( udev(7) ). --noheadings . --headings none|abbrev|full|0|1|2 . none 0 - . abbrev 1 - . full 2 - . --noflush I/O (flush) thin-pool thin-pool . --nolockfs . --noopencount (open reference count) . --noudevrules udev . --noudevsync udev . -o|--options options . --readahead [+]sectors|auto|none (read ahead) . auto . + . none . -r|--readonly . -S|--select selection selection . "selected" ( -o selected) selection 1 0 . . : dmsetup info -c -S help --table table . . --udevcookie cookie (cookie) udev. : . . -u|--uuid uuid uuid. -y|--yes . -v|--verbose [-v|--verbose] . (-vvvv): -vv -vvv ioctl -vvvv . --verifyudev udev udev . --version . (COMMANDS) clear device_name device_name . create device_name [-n|--notable|--table table|table_file] [--readahead [+]sectors|auto|none] [-u|--uuid uuid] [--addnodeoncreate| --addnodeonresume] . table table_file (live) . --notable . uuid dmsetup device_name . /dev/mapper/device_name . . create --concise [concise_device_specification] . : name, uuid, minor number, flags, comma-separated table lines. - (rw) (ro) . Uuid minor number flags . - . - . (CONCISE FORMAT) . deps [-o options] [device_name ...] . : devno ( major minor ) blkdevname ( ) devname ( blkdevname). help [-c|-C|--columns] . info [device_name ...] : State: SUSPENDED|ACTIVE, READ-ONLY Read Ahead: sectors Tables present: LIVE and/or INACTIVE Open reference count Last event sequence number (used by wait) Major and minor device number Number of targets in the live table UUID info -c|-C|--columns [--count count] [--interval seconds] [--noheadings|--headings none|abbrev|full|0|1|2] [-o fields] [-O|--sort sort_fields] [--nameprefixes] [--separator separator] [device_name] . : name, major, minor, attr, open, segments, events, uuid. : (L)ive, (I)nactive, (s)uspended, (r)ead-only, read-(w)rite. '+' . '-' . ls [--target target_type] [-o options] [--exec command] [--tree] . . . . : devno ( major minor ) blkdevname ( ) devname ( blkdevname). --tree . . : device / nodevice; blkdevname; active, open, rw, uuid. : ascii, utf, vt100; compact, inverted, notrunc. reload device_name [--table table|table_file] table table_file device_name. . mangle [device_name ...] device_name UUID (mangled) ( udev) . --manglename . UUID UUID . UUID ( --manglename ). measure [device_name ...] device_name IMA . . message device_name sector message (target). 0 . mknodes [device_name ...] /dev/mapper device_name . device_name /dev/mapper . remove [-f|--force] [--retry] [--deferred] device_name ... . dmsetup . (open) --force I/O . --deferred - . 4.27.0 3.13 . ( dmsetup version .) udev --retry . --force --udevcookie udev udev . remove_all [-f|--force] [--deferred] (reset). mknodes . ! --force I/O . --deferred - . 4.27.0 3.13 . rename device_name new_name . rename device_name --setuuid uuid uuid uuid . uuid . resume device_name ... [--addnodeoncreate|--addnodeonresume] [--noflush] [--nolockfs] [--readahead [+]sectors|auto|none] . . I/O . setgeometry device_name cyl head sect start C/H/S. splitname device_name [subsystem] (device name) subsystem . LVM . LVM (Volume Group) (Logical Volume) . . . stats command [options] IO . dmstats(8) . status [--target target_type] [--noflush] [device_name ...] . --target . --noflush thin ( 1.3.0) . suspend device_name ... [--nolockfs] [--noflush] . I/O (flush) . I/O . (sync) --nolockfs . multipath ( ) --noflush . I/O . table [--concise] [--target target_type] [--showkeys] [device_name ...] create load . --target . crypt integrity --showkeys . : ( crypt). --concise . uuid ('ro' 'rw') ( ) . - . - . (CONCISE FORMAT) . targets . udevcomplete cookie udev . udevcomplete_all [age_in_minutes] . . udevcookie . (0x0D4D) . udevcreatecookie udev . . dmsetup . . --udevcookie . dmsetup DM_UDEV_COOKIE (export) . udevreleasecookie . udevflags cookie cookie udev . udev . : DM_UDEV_FLAG_ = '1' DM_UDEV_FLAG = '1' . udev : DM_SUBSYSTEM_UDEV_FLAG = '1'. . udev . udevreleasecookie [cookie] udev . DM_UDEV_COOKIE . version . wait device_name [--noflush] [event_nr] device_name event_nr (sleep). -v . info . --noflush thin ( 1.3.0) . wipe_table device_name ... [-f|--force] [--noflush] [--nolockfs] I/O I/O . () . (TABLE FORMAT) (target) : logical_start_sector num_sectors target_type target_args : linear destination_device start_sector . striped num_stripes chunk_size [destination start_sector] ... (striped). striped 2 32 /dev/hda1 0 /dev/hdb1 0 (16 KiB) : LV chunk 1 -> hda1, chunk 1 LV chunk 2 -> hdb1, chunk 1 LV chunk 3 -> hda1, chunk 2 LV chunk 4 -> hdb1, chunk 2 . error I/O . (hole) . zero . . /dev/zero null(4) . : cache ( ) ( SSD) . crypt API (crypto API). delay / . . flakey linear . . mirror (mirror) . multipath . raid RAID md . snapshot ( ) . thin, thin-pool (thin provisioning) . Documentation/device-mapper . ( device-mapper .) (EXAMPLES) # A table to join two disks together 0 1028160 linear /dev/hda 0 1028160 3903762 linear /dev/hdb 0 # A table to stripe across the two disks, # and add the spare space from # hdb to the back of the volume 0 2056320 striped 2 32 /dev/hda 0 /dev/hdb 0 2056320 2875602 linear /dev/hdb 1028160 (CONCISE FORMAT) : o . o - . : ,,,,[,
+][;,,,,
[,
+]] : name . uuid UUID (). minor (minor) . . flags : ro rw - () table . <<>> . (EXAMPLES) # A simple linear read-only device test-linear-small,,,ro,\ 0 2097152 linear /dev/loop0 0,\ 2097152 2097152 linear /dev/loop1 0 # Two linear devices test-linear-small,,,,\ 0 2097152 linear /dev/loop0 0;\ test-linear-large,,,,\ 0 2097152 linear /dev/loop1 0,\ 2097152 2097152 linear /dev/loop2 0 (ENVIRONMENT VARIABLES) DM_DEV_DIR . "/dev" . DM_UDEV_COOKIE udev. --udevcookie . DM_DEFAULT_NAME_MANGLING_MODE (mangling). "auto" --manglename . DM_DEBUG_WITH_LINE_NUMBERS 1 . -vvvv . (AUTHORS) : Joe Thornber (SEE ALSO) dmstats(8), udev(7), udevadm(8) LVM2: : Linux Mar 26 2025 DMSETUP(8)