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mdadm: Fix mdadm -r remove option regression
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64c4757e 1/*
9a9dab36 2 * mdadm - manage Linux "md" devices aka RAID arrays.
64c4757e 3 *
c61b1c0b 4 * Copyright (C) 2001-2016 Neil Brown <neilb@suse.com>
25cfca31 5 * Copyright (C) 2016-2017 Jes Sorensen <Jes.Sorensen@gmail.com>
64c4757e
NB
6 *
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
21 *
22 * Author: Neil Brown
fffdbe5e 23 * Email: <neilb@suse.de>
25cfca31
JS
24 * Maintainer: Jes Sorensen
25 * Email: <Jes.Sorensen@gmail.com>
64c4757e
NB
26 */
27
9a9dab36 28#include "mdadm.h"
64c4757e 29
b379508e 30#ifndef VERSION
e30ca260 31#define VERSION "4.2"
b379508e
N
32#endif
33#ifndef VERS_DATE
e30ca260 34#define VERS_DATE "2021-12-30"
b379508e 35#endif
03ab9763
TM
36#ifndef EXTRAVERSION
37#define EXTRAVERSION ""
38#endif
39char Version[] = "mdadm - v" VERSION " - " VERS_DATE EXTRAVERSION "\n";
4b1ac34b 40
64c4757e
NB
41/*
42 * File: ReadMe.c
43 *
44 * This file contains general comments about the implementation
9a9dab36 45 * and the various usage messages that can be displayed by mdadm
64c4757e 46 *
64c4757e
NB
47 */
48
49/*
dd0781e5 50 * mdadm has 7 major modes of operation:
64c4757e 51 * 1/ Create
5787fa49 52 * This mode is used to create a new array with a superblock
64c4757e
NB
53 * 2/ Assemble
54 * This mode is used to assemble the parts of a previously created
55 * array into an active array. Components can be explicitly given
58380584 56 * or can be searched for. mdadm (optionally) checks that the components
5787fa49 57 * do form a bona-fide array, and can, on request, fiddle superblock
64c4757e
NB
58 * version numbers so as to assemble a faulty array.
59 * 3/ Build
60 * This is for building legacy arrays without superblocks
61 * 4/ Manage
e0d19036
NB
62 * This is for doing something to one or more devices
63 * in an array, such as add,remove,fail.
64 * run/stop/readonly/readwrite are also available
65 * 5/ Misc
66 * This is for doing things to individual devices.
67 * They might be parts of an array so
68 * zero-superblock, examine might be appropriate
69 * They might be md arrays so
70 * run,stop,rw,ro,detail might be appropriate
71 * Also query will treat it as either
72 * 6/ Monitor
73 * This mode never exits but just monitors arrays and reports changes.
dd0781e5
NB
74 * 7/ Grow
75 * This mode allows for changing of key attributes of a raid array, such
76 * as size, number of devices, and possibly even layout.
58380584
N
77 * 8/ Incremental
78 * Is assembles an array incrementally instead of all at once.
79 * As devices are discovered they can be passed to "mdadm --incremental"
80 * which will collect them. When enough devices to for an array are
81 * found, it is started.
64c4757e
NB
82 */
83
190dc029 84char short_options[]="-ABCDEFGIQhVXYWZ:vqbc:i:l:p:m:n:x:u:c:d:z:U:N:sarfRSow1tye:k:";
6c9d9260 85char short_monitor_options[]="-ABCDEFGIQhVXYWZ:vqbc:i:l:p:m:r:n:x:u:c:d:z:U:N:safRSow1tye:k:";
024768c4 86char short_bitmap_options[]=
190dc029 87 "-ABCDEFGIQhVXYWZ:vqb:c:i:l:p:m:n:x:u:c:d:z:U:N:sarfRSow1tye:k:";
8382f19b 88char short_bitmap_auto_options[]=
190dc029 89 "-ABCDEFGIQhVXYWZ:vqb:c:i:l:p:m:n:x:u:c:d:z:U:N:sa:rfRSow1tye:k:";
773135f5 90
64c4757e 91struct option long_options[] = {
1c7a808c
N
92 {"manage", 0, 0, ManageOpt},
93 {"misc", 0, 0, MiscOpt},
64c4757e
NB
94 {"assemble", 0, 0, 'A'},
95 {"build", 0, 0, 'B'},
96 {"create", 0, 0, 'C'},
97 {"detail", 0, 0, 'D'},
98 {"examine", 0, 0, 'E'},
52826846 99 {"follow", 0, 0, 'F'},
dd0781e5 100 {"grow", 0, 0, 'G'},
8382f19b 101 {"incremental",0,0, 'I'},
f7d3febc 102 {"zero-superblock", 0, 0, KillOpt}, /* deliberately not a short_option */
e0d19036 103 {"query", 0, 0, 'Q'},
c82f047c 104 {"examine-bitmap", 0, 0, 'X'},
1f48664b 105 {"auto-detect", 0, 0, AutoDetect},
4cce4069 106 {"detail-platform", 0, 0, DetailPlatform},
33414a01 107 {"kill-subarray", 1, 0, KillSubarray},
aa534678 108 {"update-subarray", 1, 0, UpdateSubarray},
20b60dcd 109 {"udev-rules", 2, 0, UdevRules},
08ca2adf 110 {"offroot", 0, 0, OffRootOpt},
6d388a88 111 {"examine-badblocks", 0, 0, ExamineBB},
52826846 112
74db60b0
N
113 {"dump", 1, 0, Dump},
114 {"restore", 1, 0, Restore},
115
52826846
NB
116 /* synonyms */
117 {"monitor", 0, 0, 'F'},
aba69144 118
64c4757e 119 /* after those will normally come the name of the md device */
58380584 120
64c4757e 121 {"help", 0, 0, 'h'},
1c7a808c 122 {"help-options",0,0, HelpOptions},
64c4757e
NB
123 {"version", 0, 0, 'V'},
124 {"verbose", 0, 0, 'v'},
dab6685f 125 {"quiet", 0, 0, 'q'},
64c4757e
NB
126
127 /* For create or build: */
1c7a808c
N
128 {"chunk", 1, 0, ChunkSize},
129 {"rounding", 1, 0, ChunkSize}, /* for linear, chunk is really a
130 * rounding number */
98c6faba 131 {"level", 1, 0, 'l'}, /* 0,1,4,5,6,linear */
1c7a808c
N
132 {"parity", 1, 0, Layout}, /* {left,right}-{a,}symmetric */
133 {"layout", 1, 0, Layout},
64c4757e 134 {"raid-disks",1, 0, 'n'},
b83d95f3 135 {"raid-devices",1, 0, 'n'},
64c4757e 136 {"spare-disks",1,0, 'x'},
b83d95f3 137 {"spare-devices",1,0, 'x'},
dd0781e5 138 {"size", 1, 0, 'z'},
1c7a808c 139 {"auto", 1, 0, Auto}, /* also for --assemble */
997aed5d 140 {"assume-clean",0,0, AssumeClean },
f9ce90ba 141 {"metadata", 1, 0, 'e'}, /* superblock format */
1c7a808c 142 {"bitmap", 1, 0, Bitmap},
997aed5d
NB
143 {"bitmap-chunk", 1, 0, BitmapChunk},
144 {"write-behind", 2, 0, WriteBehind},
1c7a808c 145 {"write-mostly",0, 0, WriteMostly},
71574efb
N
146 {"failfast", 0, 0, FailFast},
147 {"nofailfast",0, 0, NoFailFast},
997aed5d
NB
148 {"re-add", 0, 0, ReAdd},
149 {"homehost", 1, 0, HomeHost},
38098016 150 {"symlinks", 1, 0, Symlinks},
40c9a66a 151 {"data-offset",1, 0, DataOffset},
7e6e839a 152 {"nodes",1, 0, Nodes}, /* also for --assemble */
7716570e 153 {"home-cluster",1, 0, ClusterName},
cc1799c3 154 {"write-journal",1, 0, WriteJournal},
5308f117 155 {"consistency-policy", 1, 0, 'k'},
64c4757e
NB
156
157 /* For assemble */
158 {"uuid", 1, 0, 'u'},
1c7a808c 159 {"super-minor",1,0, SuperMinor},
947fd4dd 160 {"name", 1, 0, 'N'},
1c7a808c 161 {"config", 1, 0, ConfigFile},
64c4757e 162 {"scan", 0, 0, 's'},
1c7a808c 163 {"force", 0, 0, Force},
5787fa49 164 {"update", 1, 0, 'U'},
b76b30e0 165 {"freeze-reshape", 0, 0, FreezeReshape},
dfd4d8ee 166
64c4757e 167 /* Management */
1c7a808c 168 {"add", 0, 0, Add},
f33a71f1 169 {"add-spare", 0, 0, AddSpare},
01290056 170 {"add-journal", 0, 0, AddJournal},
1c7a808c
N
171 {"remove", 0, 0, Remove},
172 {"fail", 0, 0, Fail},
173 {"set-faulty",0, 0, Fail},
70c55e36
N
174 {"replace", 0, 0, Replace},
175 {"with", 0, 0, With},
64c4757e
NB
176 {"run", 0, 0, 'R'},
177 {"stop", 0, 0, 'S'},
178 {"readonly", 0, 0, 'o'},
179 {"readwrite", 0, 0, 'w'},
997aed5d 180 {"no-degraded",0,0, NoDegraded },
1c7a808c 181 {"wait", 0, 0, WaitOpt},
1770662b 182 {"wait-clean", 0, 0, Waitclean },
a740cf64 183 {"action", 1, 0, Action },
4de90913 184 {"cluster-confirm", 0, 0, ClusterConfirm},
52826846 185
cd29a5c8 186 /* For Detail/Examine */
1c7a808c 187 {"brief", 0, 0, Brief},
d11abe4b 188 {"no-devices",0, 0, NoDevices},
54bad364 189 {"export", 0, 0, 'Y'},
997aed5d 190 {"sparc2.2", 0, 0, Sparc22},
feb716e9 191 {"test", 0, 0, 't'},
c2ecf5f6 192 {"prefer", 1, 0, Prefer},
cd29a5c8 193
52826846 194 /* For Follow/monitor */
1c7a808c
N
195 {"mail", 1, 0, EMail},
196 {"program", 1, 0, ProgramOpt},
197 {"alert", 1, 0, ProgramOpt},
198 {"increment", 1, 0, Increment},
52826846 199 {"delay", 1, 0, 'd'},
1c7a808c
N
200 {"daemonise", 0, 0, Fork},
201 {"daemonize", 0, 0, Fork},
aa88f531 202 {"oneshot", 0, 0, '1'},
b5e64645 203 {"pid-file", 1, 0, 'i'},
90cf1ddd 204 {"syslog", 0, 0, 'y'},
edde9560
AC
205 {"no-sharing", 0, 0, NoSharing},
206
06b0d786 207 /* For Grow */
997aed5d 208 {"backup-file", 1,0, BackupFile},
87f26d14 209 {"invalid-backup",0,0,InvalidBackup},
84e11361 210 {"array-size", 1, 0, 'Z'},
2dddadb0 211 {"continue", 0, 0, Continue},
8382f19b
NB
212
213 /* For Incremental */
1c7a808c 214 {"rebuild-map", 0, 0, RebuildMapOpt},
950bc344
PC
215 {"path", 1, 0, IncrementalPath},
216
64c4757e
NB
217 {0, 0, 0, 0}
218};
219
220char Usage[] =
9a9dab36 221"Usage: mdadm --help\n"
64c4757e
NB
222" for help\n"
223;
224
225char Help[] =
e5a5d81e
NB
226"mdadm is used for building, managing, and monitoring\n"
227"Linux md devices (aka RAID arrays)\n"
9a9dab36 228"Usage: mdadm --create device options...\n"
e5a5d81e 229" Create a new array from unused devices.\n"
9a9dab36 230" mdadm --assemble device options...\n"
e968ba60 231" Assemble a previously created array.\n"
9a9dab36 232" mdadm --build device options...\n"
e5a5d81e 233" Create or assemble an array without metadata.\n"
e0d19036 234" mdadm --manage device options...\n"
e968ba60 235" make changes to an existing array.\n"
e0d19036 236" mdadm --misc options... devices\n"
e968ba60 237" report on or modify various md related devices.\n"
8382f19b
NB
238" mdadm --grow options device\n"
239" resize/reshape an active array\n"
240" mdadm --incremental device\n"
29ba4804 241" add/remove a device to/from an array as appropriate\n"
e0d19036 242" mdadm --monitor options...\n"
e968ba60 243" Monitor one or more array for significant changes.\n"
9a9dab36 244" mdadm device options...\n"
e968ba60 245" Shorthand for --manage.\n"
e5a5d81e
NB
246"Any parameter that does not start with '-' is treated as a device name\n"
247"or, for --examine-bitmap, a file name.\n"
248"The first such name is often the name of an md device. Subsequent\n"
249"names are often names of component devices.\n"
250"\n"
56eedc1a 251" For detailed help on the above major modes use --help after the mode\n"
e0d19036 252" e.g.\n"
9a9dab36 253" mdadm --assemble --help\n"
56eedc1a
NB
254" For general help on options use\n"
255" mdadm --help-options\n"
256;
257
258char OptionHelp[] =
64c4757e 259"Any parameter that does not start with '-' is treated as a device name\n"
c82f047c 260"or, for --examine-bitmap, a file name.\n"
e0d19036 261"The first such name is often the name of an md device. Subsequent\n"
e5a5d81e 262"names are often names of component devices.\n"
52826846 263"\n"
e0d19036 264"Some common options are:\n"
56eedc1a 265" --help -h : General help message or, after above option,\n"
64c4757e 266" mode specific help message\n"
56eedc1a 267" --help-options : This help message\n"
9a9dab36 268" --version -V : Print version information for mdadm\n"
64c4757e 269" --verbose -v : Be more verbose about what is happening\n"
dab6685f 270" --quiet -q : Don't print un-necessary messages\n"
e0d19036 271" --brief -b : Be less verbose, more brief\n"
e50cf220
MN
272" --export -Y : With --detail, --detail-platform or --examine use\n"
273" key=value format for easy import into environment\n"
e0d19036
NB
274" --force -f : Override normal checks and be more forceful\n"
275"\n"
276" --assemble -A : Assemble an array\n"
e5a5d81e 277" --build -B : Build an array without metadata\n"
e0d19036
NB
278" --create -C : Create a new array\n"
279" --detail -D : Display details of an array\n"
5787fa49 280" --examine -E : Examine superblock on an array component\n"
c82f047c 281" --examine-bitmap -X: Display the detail of a bitmap file\n"
6d388a88 282" --examine-badblocks: Display list of known bad blocks on device\n"
e0d19036 283" --monitor -F : monitor (follow) some arrays\n"
8382f19b 284" --grow -G : resize/ reshape and array\n"
29ba4804 285" --incremental -I : add/remove a single device to/from an array as appropriate\n"
e0d19036
NB
286" --query -Q : Display general information about how a\n"
287" device relates to the md driver\n"
1f48664b 288" --auto-detect : Start arrays auto-detected by the kernel\n"
e0d19036
NB
289;
290/*
64c4757e
NB
291"\n"
292" For create or build:\n"
c82f047c 293" --bitmap= -b : File to store bitmap in - may pre-exist for --build\n"
64c4757e 294" --chunk= -c : chunk size of kibibytes\n"
5787fa49 295" --rounding= : rounding factor for linear array (==chunk size)\n"
58380584
N
296" --level= -l : raid level: 0,1,4,5,6,10,linear, or mp for create.\n"
297" : 0,1,10,mp,faulty or linear for build.\n"
98c6faba 298" --parity= -p : raid5/6 parity algorithm: {left,right}-{,a}symmetric\n"
58380584 299" --layout= : same as --parity, for RAID10: [fno]NN \n"
b83d95f3 300" --raid-devices= -n : number of active devices in array\n"
58380584 301" --spare-devices= -x: number of spare (eXtra) devices in initial array\n"
e5329c37 302" --size= -z : Size (in K) of each drive in RAID1/4/5/6/10 - optional\n"
52826846
NB
303" --force -f : Honour devices as listed on command line. Don't\n"
304" : insert a missing drive for RAID5.\n"
58380584 305" --assume-clean : Assume the array is already in-sync. This is dangerous for RAID5.\n"
c82f047c
NB
306" --bitmap-chunk= : chunksize of bitmap in bitmap file (Kilobytes)\n"
307" --delay= -d : seconds between bitmap updates\n"
dfd4d8ee 308" --write-behind= : number of simultaneous write-behind requests to allow (requires bitmap)\n"
947fd4dd 309" --name= -N : Textual name for array - max 32 characters\n"
64c4757e
NB
310"\n"
311" For assemble:\n"
c82f047c 312" --bitmap= -b : File to find bitmap information in\n"
64c4757e
NB
313" --uuid= -u : uuid of array to assemble. Devices which don't\n"
314" have this uuid are excluded\n"
52826846
NB
315" --super-minor= -m : minor number to look for in super-block when\n"
316" choosing devices to use.\n"
947fd4dd 317" --name= -N : Array name to look for in super-block.\n"
64c4757e
NB
318" --config= -c : config file\n"
319" --scan -s : scan config file for missing information\n"
320" --force -f : Assemble the array even if some superblocks appear out-of-date\n"
cbfbcb0b 321" --update= -U : Update superblock: try '-A --update=?' for list of options.\n"
b8a8ccf9 322" --no-degraded : Do not start any degraded arrays - default unless --scan.\n"
64c4757e 323"\n"
cd29a5c8
NB
324" For detail or examine:\n"
325" --brief -b : Just print device name and UUID\n"
326"\n"
52826846
NB
327" For follow/monitor:\n"
328" --mail= -m : Address to mail alerts of failure to\n"
329" --program= -p : Program to run when an event is detected\n"
330" --alert= : same as --program\n"
331" --delay= -d : seconds of delay between polling state. default=60\n"
332"\n"
64c4757e
NB
333" General management:\n"
334" --add -a : add, or hotadd subsequent devices\n"
58380584 335" --re-add : re-add a recently removed device\n"
64c4757e 336" --remove -r : remove subsequent devices\n"
58380584 337" --fail -f : mark subsequent devices as faulty\n"
64c4757e 338" --set-faulty : same as --fail\n"
70c55e36 339" --replace : mark a device for replacement\n"
64c4757e 340" --run -R : start a partially built array\n"
5787fa49 341" --stop -S : deactivate array, releasing all resources\n"
64c4757e
NB
342" --readonly -o : mark array as readonly\n"
343" --readwrite -w : mark array as readwrite\n"
9a9dab36 344" --zero-superblock : erase the MD superblock from a device.\n"
b90c0e9a 345" --wait -W : wait for recovery/resync/reshape to finish.\n"
64c4757e 346;
e0d19036 347*/
64c4757e
NB
348
349char Help_create[] =
5c1dec3e 350"Usage: mdadm --create device --chunk=X --level=Y --raid-devices=Z devices\n"
64c4757e 351"\n"
aa88f531
NB
352" This usage will initialise a new md array, associate some\n"
353" devices with it, and activate the array. In order to create an\n"
354" array with some devices missing, use the special word 'missing' in\n"
355" place of the relevant device name.\n"
64c4757e 356"\n"
aa88f531 357" Before devices are added, they are checked to see if they already contain\n"
e0d19036 358" raid superblocks or filesystems. They are also checked to see if\n"
64c4757e 359" the variance in device size exceeds 1%.\n"
aa88f531
NB
360" If any discrepancy is found, the user will be prompted for confirmation\n"
361" before the array is created. The presence of a '--run' can override this\n"
64c4757e
NB
362" caution.\n"
363"\n"
e0d19036
NB
364" If the --size option is given then only that many kilobytes of each\n"
365" device is used, no matter how big each device is.\n"
682c7051 366" If no --size is given, the apparent size of the smallest drive given\n"
e0d19036
NB
367" is used for raid level 1 and greater, and the full device is used for\n"
368" other levels.\n"
682c7051 369"\n"
e0d19036 370" Options that are valid with --create (-C) are:\n"
5308f117
AP
371" --bitmap= -b : Create a bitmap for the array with the given filename\n"
372" : or an internal bitmap if 'internal' is given\n"
373" --chunk= -c : chunk size in kibibytes\n"
374" --rounding= : rounding factor for linear array (==chunk size)\n"
375" --level= -l : raid level: 0,1,4,5,6,10,linear,multipath and synonyms\n"
376" --parity= -p : raid5/6 parity algorithm: {left,right}-{,a}symmetric\n"
377" --layout= : same as --parity, for RAID10: [fno]NN \n"
378" --raid-devices= -n : number of active devices in array\n"
379" --spare-devices= -x : number of spare (eXtra) devices in initial array\n"
380" --size= -z : Size (in K) of each drive in RAID1/4/5/6/10 - optional\n"
381" --data-offset= : Space to leave between start of device and start\n"
382" : of array data.\n"
383" --force -f : Honour devices as listed on command line. Don't\n"
384" : insert a missing drive for RAID5.\n"
385" --run -R : insist of running the array even if not all\n"
386" : devices are present or some look odd.\n"
387" --readonly -o : start the array readonly - not supported yet.\n"
388" --name= -N : Textual name for array - max 32 characters\n"
389" --bitmap-chunk= : bitmap chunksize in Kilobytes.\n"
390" --delay= -d : bitmap update delay in seconds.\n"
391" --write-journal= : Specify journal device for RAID-4/5/6 array\n"
392" --consistency-policy= : Specify the policy that determines how the array\n"
393" -k : maintains consistency in case of unexpected shutdown.\n"
64c4757e
NB
394"\n"
395;
396
397char Help_build[] =
b83d95f3 398"Usage: mdadm --build device -chunk=X --level=Y --raid-devices=Z devices\n"
64c4757e
NB
399"\n"
400" This usage is similar to --create. The difference is that it creates\n"
e0d19036 401" a legacy array without a superblock. With these arrays there is no\n"
64c4757e
NB
402" different between initially creating the array and subsequently\n"
403" assembling the array, except that hopefully there is useful data\n"
404" there in the second case.\n"
405"\n"
58380584 406" The level may only be 0, 1, 10, linear, multipath, or faulty.\n"
64c4757e 407" All devices must be listed and the array will be started once complete.\n"
e0d19036 408" Options that are valid with --build (-B) are:\n"
c82f047c 409" --bitmap= : file to store/find bitmap information in.\n"
e0d19036 410" --chunk= -c : chunk size of kibibytes\n"
5787fa49 411" --rounding= : rounding factor for linear array (==chunk size)\n"
58380584 412" --level= -l : 0, 1, 10, linear, multipath, faulty\n"
c82f047c
NB
413" --raid-devices= -n : number of active devices in array\n"
414" --bitmap-chunk= : bitmap chunksize in Kilobytes.\n"
415" --delay= -d : bitmap update delay in seconds.\n"
64c4757e
NB
416;
417
418char Help_assemble[] =
9a9dab36
NB
419"Usage: mdadm --assemble device options...\n"
420" mdadm --assemble --scan options...\n"
64c4757e
NB
421"\n"
422"This usage assembles one or more raid arrays from pre-existing\n"
423"components.\n"
e0d19036 424"For each array, mdadm needs to know the md device, the identity of\n"
52826846
NB
425"the array, and a number of sub devices. These can be found in a number\n"
426"of ways.\n"
427"\n"
58380584
N
428"The md device is given on the command line, is found listed in the\n"
429"config file, or can be deduced from the array identity.\n"
430"The array identity is determined either from the --uuid, --name, or\n"
431"--super-minor commandline arguments, from the config file,\n"
52826846 432"or from the first component device on the command line.\n"
64c4757e 433"\n"
52826846
NB
434"The different combinations of these are as follows:\n"
435" If the --scan option is not given, then only devices and identities\n"
436" listed on the command line are considered.\n"
e0d19036 437" The first device will be the array device, and the remainder will be\n"
52826846
NB
438" examined when looking for components.\n"
439" If an explicit identity is given with --uuid or --super-minor, then\n"
e0d19036 440" only devices with a superblock which matches that identity is considered,\n"
52826846 441" otherwise every device listed is considered.\n"
64c4757e 442"\n"
52826846
NB
443" If the --scan option is given, and no devices are listed, then\n"
444" every array listed in the config file is considered for assembly.\n"
e0d19036 445" The identity of candidate devices are determined from the config file.\n"
58380584
N
446" After these arrays are assembled, mdadm will look for other devices\n"
447" that could form further arrays and tries to assemble them. This can\n"
448" be disabled using the 'AUTO' option in the config file.\n"
64c4757e 449"\n"
52826846
NB
450" If the --scan option is given as well as one or more devices, then\n"
451" Those devices are md devices that are to be assembled. Their identity\n"
452" and components are determined from the config file.\n"
64c4757e 453"\n"
b8a8ccf9
NB
454" If mdadm can not find all of the components for an array, it will assemble\n"
455" it but not activate it unless --run or --scan is given. To preserve this\n"
456" behaviour even with --scan, add --no-degraded. Note that \"all of the\n"
457" components\" means as many as were present the last time the array was running\n"
458" as recorded in the superblock. If the array was already degraded, and\n"
459" the missing device is not a new problem, it will still be assembled. It\n"
460" is only newly missing devices that cause the array not to be started.\n"
461"\n"
e0d19036 462"Options that are valid with --assemble (-A) are:\n"
58380584 463" --bitmap= : bitmap file to use with the array\n"
e0d19036
NB
464" --uuid= -u : uuid of array to assemble. Devices which don't\n"
465" have this uuid are excluded\n"
466" --super-minor= -m : minor number to look for in super-block when\n"
467" choosing devices to use.\n"
947fd4dd 468" --name= -N : Array name to look for in super-block.\n"
e0d19036
NB
469" --config= -c : config file\n"
470" --scan -s : scan config file for missing information\n"
471" --run -R : Try to start the array even if not enough devices\n"
472" for a full array are present\n"
473" --force -f : Assemble the array even if some superblocks appear\n"
474" : out-of-date. This involves modifying the superblocks.\n"
cbfbcb0b 475" --update= -U : Update superblock: try '-A --update=?' for option list.\n"
b8a8ccf9 476" --no-degraded : Assemble but do not start degraded arrays.\n"
0ea8f5b1 477" --readonly -o : Mark the array as read-only. No resync will start.\n"
e0d19036
NB
478;
479
480char Help_manage[] =
481"Usage: mdadm arraydevice options component devices...\n"
482"\n"
483"This usage is for managing the component devices within an array.\n"
484"The --manage option is not needed and is assumed if the first argument\n"
485"is a device name or a management option.\n"
58380584 486"The first device listed will be taken to be an md array device, any\n"
e0d19036
NB
487"subsequent devices are (potential) components of that array.\n"
488"\n"
489"Options that are valid with management mode are:\n"
490" --add -a : hotadd subsequent devices to the array\n"
58380584
N
491" --re-add : subsequent devices are re-added if there were\n"
492" : recent members of the array\n"
e0d19036
NB
493" --remove -r : remove subsequent devices, which must not be active\n"
494" --fail -f : mark subsequent devices a faulty\n"
495" --set-faulty : same as --fail\n"
70c55e36
N
496" --replace : mark device(s) to be replaced by spares. Once\n"
497" : replacement completes, device will be marked faulty\n"
498" --with : Indicate which spare a previous '--replace' should\n"
499" : prefer to use\n"
e0d19036 500" --run -R : start a partially built array\n"
5787fa49 501" --stop -S : deactivate array, releasing all resources\n"
e0d19036
NB
502" --readonly -o : mark array as readonly\n"
503" --readwrite -w : mark array as readwrite\n"
504;
505
506char Help_misc[] =
507"Usage: mdadm misc_option devices...\n"
508"\n"
509"This usage is for performing some task on one or more devices, which\n"
510"may be arrays or components, depending on the task.\n"
511"The --misc option is not needed (though it is allowed) and is assumed\n"
512"if the first argument in a misc option.\n"
513"\n"
514"Options that are valid with the miscellaneous mode are:\n"
515" --query -Q : Display general information about how a\n"
516" device relates to the md driver\n"
517" --detail -D : Display details of an array\n"
4cce4069 518" --detail-platform : Display hardware/firmware details\n"
5787fa49 519" --examine -E : Examine superblock on an array component\n"
c82f047c 520" --examine-bitmap -X: Display contents of a bitmap file\n"
6d388a88 521" --examine-badblocks: Display list of known bad blocks on device\n"
e0d19036
NB
522" --zero-superblock : erase the MD superblock from a device.\n"
523" --run -R : start a partially built array\n"
5787fa49 524" --stop -S : deactivate array, releasing all resources\n"
e0d19036
NB
525" --readonly -o : mark array as readonly\n"
526" --readwrite -w : mark array as readwrite\n"
feb716e9 527" --test -t : exit status 0 if ok, 1 if degrade, 2 if dead, 4 if missing\n"
b90c0e9a 528" --wait -W : wait for resync/rebuild/recovery to finish\n"
a740cf64 529" --action= : initiate or abort ('idle' or 'frozen') a 'check' or 'repair'.\n"
e0d19036
NB
530;
531
532char Help_monitor[] =
533"Usage: mdadm --monitor options devices\n"
534"\n"
535"This usage causes mdadm to monitor a number of md arrays by periodically\n"
536"polling their status and acting on any changes.\n"
537"If any devices are listed then those devices are monitored, otherwise\n"
538"all devices listed in the config file are monitored.\n"
539"The address for mailing advisories to, and the program to handle\n"
540"each change can be specified in the config file or on the command line.\n"
58380584
N
541"There must be at least one destination for advisories, whether\n"
542"an email address, a program, or --syslog\n"
e0d19036 543"\n"
dd0781e5 544"Options that are valid with the monitor (-F --follow) mode are:\n"
e0d19036
NB
545" --mail= -m : Address to mail alerts of failure to\n"
546" --program= -p : Program to run when an event is detected\n"
547" --alert= : same as --program\n"
237d8790 548" --syslog -y : Report alerts via syslog\n"
9a36a9b7 549" --increment= -r : Report RebuildNN events in the given increment. default=20\n"
e0d19036
NB
550" --delay= -d : seconds of delay between polling state. default=60\n"
551" --config= -c : specify a different config file\n"
552" --scan -s : find mail-address/program in config file\n"
d013a55e 553" --daemonise -f : Fork and continue in child, parent exits\n"
b5e64645 554" --pid-file= -i : In daemon mode write pid to specified file instead of stdout\n"
aa88f531 555" --oneshot -1 : Check for degraded arrays, then exit\n"
98c6faba 556" --test -t : Generate a TestMessage event against each array at startup\n"
e0d19036
NB
557;
558
dd0781e5
NB
559char Help_grow[] =
560"Usage: mdadm --grow device options\n"
561"\n"
562"This usage causes mdadm to attempt to reconfigure a running array.\n"
563"This is only possibly if the kernel being used supports a particular\n"
58380584 564"reconfiguration.\n"
dd0781e5 565"\n"
891d2994 566"Options that are valid with the grow (-G --grow) mode are:\n"
860f11ed
AP
567" --level= -l : Tell mdadm what level to convert the array to.\n"
568" --layout= -p : For a FAULTY array, set/change the error mode.\n"
569" : for other arrays, update the layout\n"
570" --size= -z : Change the active size of devices in an array.\n"
571" : This is useful if all devices have been replaced\n"
572" : with larger devices. Value is in Kilobytes, or\n"
573" : the special word 'max' meaning 'as large as possible'.\n"
574" --assume-clean : When increasing the --size, this flag will avoid\n"
575" : a resync of the new space\n"
576" --chunk= -c : Change the chunksize of the array\n"
577" --raid-devices= -n : Change the number of active devices in an array.\n"
578" --add= -a : Add listed devices as part of reshape. This is\n"
579" : needed for resizing a RAID0 which cannot have\n"
580" : spares already present.\n"
581" --bitmap= -b : Add or remove a write-intent bitmap.\n"
582" --backup-file= file : A file on a different device to store data for a\n"
583" : short time while increasing raid-devices on a\n"
584" : RAID4/5/6 array. Also needed throughout a reshape\n"
585" : when changing parameters other than raid-devices\n"
586" --array-size= -Z : Change visible size of array. This does not change any\n"
587" : data on the device, and is not stable across restarts.\n"
588" --data-offset= : Location on device to move start of data to.\n"
589" --consistency-policy= : Change the consistency policy of an active array.\n"
590" -k : Currently works only for PPL with RAID5.\n"
dd0781e5 591;
e0d19036 592
8382f19b 593char Help_incr[] =
29ba4804 594"Usage: mdadm --incremental [-Rqrsf] device\n"
8382f19b
NB
595"\n"
596"This usage allows for incremental assembly of md arrays. Devices can be\n"
597"added one at a time as they are discovered. Once an array has all expected\n"
598"devices, it will be started.\n"
599"\n"
29ba4804
N
600"Optionally, the process can be reversed by using the fail option.\n"
601"When fail mode is invoked, mdadm will see if the device belongs to an array\n"
602"and then both fail (if needed) and remove the device from that array.\n"
603"\n"
604"Options that are valid with incremental assembly (-I --incremental) are:\n"
605" --run -R : Run arrays as soon as a minimal number of devices are\n"
7e6140e6
N
606" : present rather than waiting for all expected.\n"
607" --quiet -q : Don't print any information messages, just errors.\n"
608" --rebuild-map -r : Rebuild the 'map' file that mdadm uses for tracking\n"
609" : partial arrays.\n"
610" --scan -s : Use with -R to start any arrays that have the minimal\n"
611" : required number of devices, but are not yet started.\n"
58380584
N
612" --fail -f : First fail (if needed) and then remove device from\n"
613" : any array that it is a member of.\n"
8382f19b 614;
e0d19036
NB
615
616char Help_config[] =
e0d19036 617" The config file contains, apart from blank lines and comment lines that\n"
58380584
N
618" start with a hash(#), array lines, device lines, and various\n"
619" configuration lines.\n"
620" Each line is constructed of a number of space separated words, and can\n"
621" be continued on subsequent physical lines by indenting those lines.\n"
e0d19036
NB
622"\n"
623" A device line starts with the word 'device' and then has a number of words\n"
624" which identify devices. These words should be names of devices in the\n"
625" filesystem, and can contain wildcards. There can be multiple words or each\n"
626" device line, and multiple device lines. All devices so listed are checked\n"
627" for relevant super blocks when assembling arrays.\n"
628"\n"
629" An array line start with the word 'array'. This is followed by the name of\n"
630" the array device in the filesystem, e.g. '/dev/md2'. Subsequent words\n"
631" describe the identity of the array, used to recognise devices to include in the\n"
632" array. The identity can be given as a UUID with a word starting 'uuid=', or\n"
633" as a minor-number stored in the superblock using 'super-minor=', or as a list\n"
634" of devices. This is given as a comma separated list of names, possibly\n"
5787fa49 635" containing wildcards, preceded by 'devices='. If multiple critea are given,\n"
e0d19036
NB
636" than a device must match all of them to be considered.\n"
637"\n"
58380584 638" Other configuration lines include:\n"
c2340037
LF
639" mailaddr, mailfrom, program, monitordelay used for --monitor mode\n"
640" create, auto used when creating device names in /dev\n"
641" homehost, homecluster, policy, part-policy used to guide policy in various\n"
642" situations\n"
643"\n"
644"For more details see mdadm.conf(5).\n"
64c4757e
NB
645"\n"
646;
682c7051 647
5187a385
N
648char *mode_help[mode_count] = {
649 [0] = Help,
650 [ASSEMBLE] = Help_assemble,
651 [BUILD] = Help_build,
652 [CREATE] = Help_create,
653 [MANAGE] = Help_manage,
654 [MISC] = Help_misc,
655 [MONITOR] = Help_monitor,
656 [GROW] = Help_grow,
657 [INCREMENTAL] = Help_incr,
658};