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64c4757e 1/*
9a9dab36 2 * mdadm - manage Linux "md" devices aka RAID arrays.
64c4757e 3 *
58380584 4 * Copyright (C) 2001-2012 Neil Brown <neilb@suse.de>
64c4757e
NB
5 *
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
11 *
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
20 *
21 * Author: Neil Brown
fffdbe5e 22 * Email: <neilb@suse.de>
64c4757e
NB
23 */
24
9a9dab36 25#include "mdadm.h"
64c4757e 26
3b2aad6e 27char Version[] = Name " - v3.2.5 - 18th May 2012\n";
4b1ac34b 28
64c4757e
NB
29/*
30 * File: ReadMe.c
31 *
32 * This file contains general comments about the implementation
9a9dab36 33 * and the various usage messages that can be displayed by mdadm
64c4757e 34 *
64c4757e
NB
35 */
36
37/*
dd0781e5 38 * mdadm has 7 major modes of operation:
64c4757e 39 * 1/ Create
5787fa49 40 * This mode is used to create a new array with a superblock
64c4757e
NB
41 * 2/ Assemble
42 * This mode is used to assemble the parts of a previously created
43 * array into an active array. Components can be explicitly given
58380584 44 * or can be searched for. mdadm (optionally) checks that the components
5787fa49 45 * do form a bona-fide array, and can, on request, fiddle superblock
64c4757e
NB
46 * version numbers so as to assemble a faulty array.
47 * 3/ Build
48 * This is for building legacy arrays without superblocks
49 * 4/ Manage
e0d19036
NB
50 * This is for doing something to one or more devices
51 * in an array, such as add,remove,fail.
52 * run/stop/readonly/readwrite are also available
53 * 5/ Misc
54 * This is for doing things to individual devices.
55 * They might be parts of an array so
56 * zero-superblock, examine might be appropriate
57 * They might be md arrays so
58 * run,stop,rw,ro,detail might be appropriate
59 * Also query will treat it as either
60 * 6/ Monitor
61 * This mode never exits but just monitors arrays and reports changes.
dd0781e5
NB
62 * 7/ Grow
63 * This mode allows for changing of key attributes of a raid array, such
64 * as size, number of devices, and possibly even layout.
58380584
N
65 * 8/ Incremental
66 * Is assembles an array incrementally instead of all at once.
67 * As devices are discovered they can be passed to "mdadm --incremental"
68 * which will collect them. When enough devices to for an array are
69 * found, it is started.
64c4757e
NB
70 */
71
866f509f 72char short_options[]="-ABCDEFGIQhVXYWZ:vqbc:i:l:p:m:n:x:u:c:d:z:U:N:sarfRSow1tye:";
024768c4 73char short_bitmap_options[]=
5d500228 74 "-ABCDEFGIQhVXYWZ:vqb:c:i:l:p:m:n:x:u:c:d:z:U:N:sarfRSow1tye:";
8382f19b 75char short_bitmap_auto_options[]=
5d500228 76 "-ABCDEFGIQhVXYWZ:vqb:c:i:l:p:m:n:x:u:c:d:z:U:N:sa:rfRSow1tye:";
773135f5 77
64c4757e 78struct option long_options[] = {
1c7a808c
N
79 {"manage", 0, 0, ManageOpt},
80 {"misc", 0, 0, MiscOpt},
64c4757e
NB
81 {"assemble", 0, 0, 'A'},
82 {"build", 0, 0, 'B'},
83 {"create", 0, 0, 'C'},
84 {"detail", 0, 0, 'D'},
85 {"examine", 0, 0, 'E'},
52826846 86 {"follow", 0, 0, 'F'},
dd0781e5 87 {"grow", 0, 0, 'G'},
8382f19b 88 {"incremental",0,0, 'I'},
f7d3febc 89 {"zero-superblock", 0, 0, KillOpt}, /* deliberately not a short_option */
e0d19036 90 {"query", 0, 0, 'Q'},
c82f047c 91 {"examine-bitmap", 0, 0, 'X'},
1f48664b 92 {"auto-detect", 0, 0, AutoDetect},
4cce4069 93 {"detail-platform", 0, 0, DetailPlatform},
33414a01 94 {"kill-subarray", 1, 0, KillSubarray},
aa534678 95 {"update-subarray", 1, 0, UpdateSubarray},
20b60dcd 96 {"udev-rules", 2, 0, UdevRules},
08ca2adf 97 {"offroot", 0, 0, OffRootOpt},
52826846
NB
98
99 /* synonyms */
100 {"monitor", 0, 0, 'F'},
aba69144 101
64c4757e 102 /* after those will normally come the name of the md device */
58380584 103
64c4757e 104 {"help", 0, 0, 'h'},
1c7a808c 105 {"help-options",0,0, HelpOptions},
64c4757e
NB
106 {"version", 0, 0, 'V'},
107 {"verbose", 0, 0, 'v'},
dab6685f 108 {"quiet", 0, 0, 'q'},
64c4757e
NB
109
110 /* For create or build: */
1c7a808c
N
111 {"chunk", 1, 0, ChunkSize},
112 {"rounding", 1, 0, ChunkSize}, /* for linear, chunk is really a
113 * rounding number */
98c6faba 114 {"level", 1, 0, 'l'}, /* 0,1,4,5,6,linear */
1c7a808c
N
115 {"parity", 1, 0, Layout}, /* {left,right}-{a,}symmetric */
116 {"layout", 1, 0, Layout},
64c4757e 117 {"raid-disks",1, 0, 'n'},
b83d95f3 118 {"raid-devices",1, 0, 'n'},
64c4757e 119 {"spare-disks",1,0, 'x'},
b83d95f3 120 {"spare-devices",1,0, 'x'},
dd0781e5 121 {"size", 1, 0, 'z'},
1c7a808c 122 {"auto", 1, 0, Auto}, /* also for --assemble */
997aed5d 123 {"assume-clean",0,0, AssumeClean },
f9ce90ba 124 {"metadata", 1, 0, 'e'}, /* superblock format */
1c7a808c 125 {"bitmap", 1, 0, Bitmap},
997aed5d
NB
126 {"bitmap-chunk", 1, 0, BitmapChunk},
127 {"write-behind", 2, 0, WriteBehind},
1c7a808c 128 {"write-mostly",0, 0, WriteMostly},
997aed5d
NB
129 {"re-add", 0, 0, ReAdd},
130 {"homehost", 1, 0, HomeHost},
38098016 131 {"symlinks", 1, 0, Symlinks},
40c9a66a 132 {"data-offset",1, 0, DataOffset},
64c4757e
NB
133
134 /* For assemble */
135 {"uuid", 1, 0, 'u'},
1c7a808c 136 {"super-minor",1,0, SuperMinor},
947fd4dd 137 {"name", 1, 0, 'N'},
1c7a808c 138 {"config", 1, 0, ConfigFile},
64c4757e 139 {"scan", 0, 0, 's'},
1c7a808c 140 {"force", 0, 0, Force},
5787fa49 141 {"update", 1, 0, 'U'},
b76b30e0 142 {"freeze-reshape", 0, 0, FreezeReshape},
dfd4d8ee 143
64c4757e 144 /* Management */
1c7a808c
N
145 {"add", 0, 0, Add},
146 {"remove", 0, 0, Remove},
147 {"fail", 0, 0, Fail},
148 {"set-faulty",0, 0, Fail},
64c4757e
NB
149 {"run", 0, 0, 'R'},
150 {"stop", 0, 0, 'S'},
151 {"readonly", 0, 0, 'o'},
152 {"readwrite", 0, 0, 'w'},
997aed5d 153 {"no-degraded",0,0, NoDegraded },
1c7a808c 154 {"wait", 0, 0, WaitOpt},
1770662b 155 {"wait-clean", 0, 0, Waitclean },
52826846 156
cd29a5c8 157 /* For Detail/Examine */
1c7a808c 158 {"brief", 0, 0, Brief},
54bad364 159 {"export", 0, 0, 'Y'},
997aed5d 160 {"sparc2.2", 0, 0, Sparc22},
feb716e9 161 {"test", 0, 0, 't'},
c2ecf5f6 162 {"prefer", 1, 0, Prefer},
cd29a5c8 163
52826846 164 /* For Follow/monitor */
1c7a808c
N
165 {"mail", 1, 0, EMail},
166 {"program", 1, 0, ProgramOpt},
167 {"alert", 1, 0, ProgramOpt},
168 {"increment", 1, 0, Increment},
52826846 169 {"delay", 1, 0, 'd'},
1c7a808c
N
170 {"daemonise", 0, 0, Fork},
171 {"daemonize", 0, 0, Fork},
aa88f531 172 {"oneshot", 0, 0, '1'},
b5e64645 173 {"pid-file", 1, 0, 'i'},
90cf1ddd 174 {"syslog", 0, 0, 'y'},
edde9560
AC
175 {"no-sharing", 0, 0, NoSharing},
176
06b0d786 177 /* For Grow */
997aed5d 178 {"backup-file", 1,0, BackupFile},
87f26d14 179 {"invalid-backup",0,0,InvalidBackup},
84e11361 180 {"array-size", 1, 0, 'Z'},
2dddadb0 181 {"continue", 0, 0, Continue},
8382f19b
NB
182
183 /* For Incremental */
1c7a808c 184 {"rebuild-map", 0, 0, RebuildMapOpt},
950bc344
PC
185 {"path", 1, 0, IncrementalPath},
186
64c4757e
NB
187 {0, 0, 0, 0}
188};
189
190char Usage[] =
9a9dab36 191"Usage: mdadm --help\n"
64c4757e
NB
192" for help\n"
193;
194
195char Help[] =
e5a5d81e
NB
196"mdadm is used for building, managing, and monitoring\n"
197"Linux md devices (aka RAID arrays)\n"
9a9dab36 198"Usage: mdadm --create device options...\n"
e5a5d81e 199" Create a new array from unused devices.\n"
9a9dab36 200" mdadm --assemble device options...\n"
e968ba60 201" Assemble a previously created array.\n"
9a9dab36 202" mdadm --build device options...\n"
e5a5d81e 203" Create or assemble an array without metadata.\n"
e0d19036 204" mdadm --manage device options...\n"
e968ba60 205" make changes to an existing array.\n"
e0d19036 206" mdadm --misc options... devices\n"
e968ba60 207" report on or modify various md related devices.\n"
8382f19b
NB
208" mdadm --grow options device\n"
209" resize/reshape an active array\n"
210" mdadm --incremental device\n"
29ba4804 211" add/remove a device to/from an array as appropriate\n"
e0d19036 212" mdadm --monitor options...\n"
e968ba60 213" Monitor one or more array for significant changes.\n"
9a9dab36 214" mdadm device options...\n"
e968ba60 215" Shorthand for --manage.\n"
e5a5d81e
NB
216"Any parameter that does not start with '-' is treated as a device name\n"
217"or, for --examine-bitmap, a file name.\n"
218"The first such name is often the name of an md device. Subsequent\n"
219"names are often names of component devices.\n"
220"\n"
56eedc1a 221" For detailed help on the above major modes use --help after the mode\n"
e0d19036 222" e.g.\n"
9a9dab36 223" mdadm --assemble --help\n"
56eedc1a
NB
224" For general help on options use\n"
225" mdadm --help-options\n"
226;
227
228char OptionHelp[] =
64c4757e 229"Any parameter that does not start with '-' is treated as a device name\n"
c82f047c 230"or, for --examine-bitmap, a file name.\n"
e0d19036 231"The first such name is often the name of an md device. Subsequent\n"
e5a5d81e 232"names are often names of component devices.\n"
52826846 233"\n"
e0d19036 234"Some common options are:\n"
56eedc1a 235" --help -h : General help message or, after above option,\n"
64c4757e 236" mode specific help message\n"
56eedc1a 237" --help-options : This help message\n"
9a9dab36 238" --version -V : Print version information for mdadm\n"
64c4757e 239" --verbose -v : Be more verbose about what is happening\n"
dab6685f 240" --quiet -q : Don't print un-necessary messages\n"
e0d19036 241" --brief -b : Be less verbose, more brief\n"
e50cf220
MN
242" --export -Y : With --detail, --detail-platform or --examine use\n"
243" key=value format for easy import into environment\n"
e0d19036
NB
244" --force -f : Override normal checks and be more forceful\n"
245"\n"
246" --assemble -A : Assemble an array\n"
e5a5d81e 247" --build -B : Build an array without metadata\n"
e0d19036
NB
248" --create -C : Create a new array\n"
249" --detail -D : Display details of an array\n"
5787fa49 250" --examine -E : Examine superblock on an array component\n"
c82f047c 251" --examine-bitmap -X: Display the detail of a bitmap file\n"
e0d19036 252" --monitor -F : monitor (follow) some arrays\n"
8382f19b 253" --grow -G : resize/ reshape and array\n"
29ba4804 254" --incremental -I : add/remove a single device to/from an array as appropriate\n"
e0d19036
NB
255" --query -Q : Display general information about how a\n"
256" device relates to the md driver\n"
1f48664b 257" --auto-detect : Start arrays auto-detected by the kernel\n"
08ca2adf
JS
258" --offroot : Set first character of argv[0] to @ to indicate the\n"
259" application was launched from initrd/initramfs and\n"
260" should not be shutdown by systemd as part of the\n"
261" regular shutdown process.\n"
e0d19036
NB
262;
263/*
64c4757e
NB
264"\n"
265" For create or build:\n"
c82f047c 266" --bitmap= -b : File to store bitmap in - may pre-exist for --build\n"
64c4757e 267" --chunk= -c : chunk size of kibibytes\n"
5787fa49 268" --rounding= : rounding factor for linear array (==chunk size)\n"
58380584
N
269" --level= -l : raid level: 0,1,4,5,6,10,linear, or mp for create.\n"
270" : 0,1,10,mp,faulty or linear for build.\n"
98c6faba 271" --parity= -p : raid5/6 parity algorithm: {left,right}-{,a}symmetric\n"
58380584 272" --layout= : same as --parity, for RAID10: [fno]NN \n"
b83d95f3 273" --raid-devices= -n : number of active devices in array\n"
58380584 274" --spare-devices= -x: number of spare (eXtra) devices in initial array\n"
e5329c37 275" --size= -z : Size (in K) of each drive in RAID1/4/5/6/10 - optional\n"
52826846
NB
276" --force -f : Honour devices as listed on command line. Don't\n"
277" : insert a missing drive for RAID5.\n"
58380584 278" --assume-clean : Assume the array is already in-sync. This is dangerous for RAID5.\n"
c82f047c
NB
279" --bitmap-chunk= : chunksize of bitmap in bitmap file (Kilobytes)\n"
280" --delay= -d : seconds between bitmap updates\n"
dfd4d8ee 281" --write-behind= : number of simultaneous write-behind requests to allow (requires bitmap)\n"
947fd4dd 282" --name= -N : Textual name for array - max 32 characters\n"
64c4757e
NB
283"\n"
284" For assemble:\n"
c82f047c 285" --bitmap= -b : File to find bitmap information in\n"
64c4757e
NB
286" --uuid= -u : uuid of array to assemble. Devices which don't\n"
287" have this uuid are excluded\n"
52826846
NB
288" --super-minor= -m : minor number to look for in super-block when\n"
289" choosing devices to use.\n"
947fd4dd 290" --name= -N : Array name to look for in super-block.\n"
64c4757e
NB
291" --config= -c : config file\n"
292" --scan -s : scan config file for missing information\n"
293" --force -f : Assemble the array even if some superblocks appear out-of-date\n"
cbfbcb0b 294" --update= -U : Update superblock: try '-A --update=?' for list of options.\n"
b8a8ccf9 295" --no-degraded : Do not start any degraded arrays - default unless --scan.\n"
64c4757e 296"\n"
cd29a5c8
NB
297" For detail or examine:\n"
298" --brief -b : Just print device name and UUID\n"
299"\n"
52826846
NB
300" For follow/monitor:\n"
301" --mail= -m : Address to mail alerts of failure to\n"
302" --program= -p : Program to run when an event is detected\n"
303" --alert= : same as --program\n"
304" --delay= -d : seconds of delay between polling state. default=60\n"
305"\n"
64c4757e
NB
306" General management:\n"
307" --add -a : add, or hotadd subsequent devices\n"
58380584 308" --re-add : re-add a recently removed device\n"
64c4757e 309" --remove -r : remove subsequent devices\n"
58380584 310" --fail -f : mark subsequent devices as faulty\n"
64c4757e
NB
311" --set-faulty : same as --fail\n"
312" --run -R : start a partially built array\n"
5787fa49 313" --stop -S : deactivate array, releasing all resources\n"
64c4757e
NB
314" --readonly -o : mark array as readonly\n"
315" --readwrite -w : mark array as readwrite\n"
9a9dab36 316" --zero-superblock : erase the MD superblock from a device.\n"
b90c0e9a 317" --wait -W : wait for recovery/resync/reshape to finish.\n"
64c4757e 318;
e0d19036 319*/
64c4757e
NB
320
321char Help_create[] =
b83d95f3 322"Usage: mdadm --create device -chunk=X --level=Y --raid-devices=Z devices\n"
64c4757e 323"\n"
aa88f531
NB
324" This usage will initialise a new md array, associate some\n"
325" devices with it, and activate the array. In order to create an\n"
326" array with some devices missing, use the special word 'missing' in\n"
327" place of the relevant device name.\n"
64c4757e 328"\n"
aa88f531 329" Before devices are added, they are checked to see if they already contain\n"
e0d19036 330" raid superblocks or filesystems. They are also checked to see if\n"
64c4757e 331" the variance in device size exceeds 1%.\n"
aa88f531
NB
332" If any discrepancy is found, the user will be prompted for confirmation\n"
333" before the array is created. The presence of a '--run' can override this\n"
64c4757e
NB
334" caution.\n"
335"\n"
e0d19036
NB
336" If the --size option is given then only that many kilobytes of each\n"
337" device is used, no matter how big each device is.\n"
682c7051 338" If no --size is given, the apparent size of the smallest drive given\n"
e0d19036
NB
339" is used for raid level 1 and greater, and the full device is used for\n"
340" other levels.\n"
682c7051 341"\n"
e0d19036 342" Options that are valid with --create (-C) are:\n"
c82f047c 343" --bitmap= : Create a bitmap for the array with the given filename\n"
58380584
N
344" : or an internal bitmap is 'internal' is given\n"
345" --chunk= -c : chunk size in kibibytes\n"
5787fa49 346" --rounding= : rounding factor for linear array (==chunk size)\n"
58380584 347" --level= -l : raid level: 0,1,4,5,6,10,linear,multipath and synonyms\n"
98c6faba 348" --parity= -p : raid5/6 parity algorithm: {left,right}-{,a}symmetric\n"
58380584 349" --layout= : same as --parity, for RAID10: [fno]NN \n"
b83d95f3 350" --raid-devices= -n : number of active devices in array\n"
58380584 351" --spare-devices= -x: number of spare (eXtra) devices in initial array\n"
e5329c37 352" --size= -z : Size (in K) of each drive in RAID1/4/5/6/10 - optional\n"
40c9a66a
N
353" --data-offset= : Space to leave between start of device and start\n"
354" : of array data.\n"
e0d19036
NB
355" --force -f : Honour devices as listed on command line. Don't\n"
356" : insert a missing drive for RAID5.\n"
aa88f531 357" --run -R : insist of running the array even if not all\n"
e0d19036 358" : devices are present or some look odd.\n"
aa88f531 359" --readonly -o : start the array readonly - not supported yet.\n"
947fd4dd 360" --name= -N : Textual name for array - max 32 characters\n"
c82f047c
NB
361" --bitmap-chunk= : bitmap chunksize in Kilobytes.\n"
362" --delay= -d : bitmap update delay in seconds.\n"
64c4757e
NB
363"\n"
364;
365
366char Help_build[] =
b83d95f3 367"Usage: mdadm --build device -chunk=X --level=Y --raid-devices=Z devices\n"
64c4757e
NB
368"\n"
369" This usage is similar to --create. The difference is that it creates\n"
e0d19036 370" a legacy array without a superblock. With these arrays there is no\n"
64c4757e
NB
371" different between initially creating the array and subsequently\n"
372" assembling the array, except that hopefully there is useful data\n"
373" there in the second case.\n"
374"\n"
58380584 375" The level may only be 0, 1, 10, linear, multipath, or faulty.\n"
64c4757e 376" All devices must be listed and the array will be started once complete.\n"
e0d19036 377" Options that are valid with --build (-B) are:\n"
c82f047c 378" --bitmap= : file to store/find bitmap information in.\n"
e0d19036 379" --chunk= -c : chunk size of kibibytes\n"
5787fa49 380" --rounding= : rounding factor for linear array (==chunk size)\n"
58380584 381" --level= -l : 0, 1, 10, linear, multipath, faulty\n"
c82f047c
NB
382" --raid-devices= -n : number of active devices in array\n"
383" --bitmap-chunk= : bitmap chunksize in Kilobytes.\n"
384" --delay= -d : bitmap update delay in seconds.\n"
64c4757e
NB
385;
386
387char Help_assemble[] =
9a9dab36
NB
388"Usage: mdadm --assemble device options...\n"
389" mdadm --assemble --scan options...\n"
64c4757e
NB
390"\n"
391"This usage assembles one or more raid arrays from pre-existing\n"
392"components.\n"
e0d19036 393"For each array, mdadm needs to know the md device, the identity of\n"
52826846
NB
394"the array, and a number of sub devices. These can be found in a number\n"
395"of ways.\n"
396"\n"
58380584
N
397"The md device is given on the command line, is found listed in the\n"
398"config file, or can be deduced from the array identity.\n"
399"The array identity is determined either from the --uuid, --name, or\n"
400"--super-minor commandline arguments, from the config file,\n"
52826846 401"or from the first component device on the command line.\n"
64c4757e 402"\n"
52826846
NB
403"The different combinations of these are as follows:\n"
404" If the --scan option is not given, then only devices and identities\n"
405" listed on the command line are considered.\n"
e0d19036 406" The first device will be the array device, and the remainder will be\n"
52826846
NB
407" examined when looking for components.\n"
408" If an explicit identity is given with --uuid or --super-minor, then\n"
e0d19036 409" only devices with a superblock which matches that identity is considered,\n"
52826846 410" otherwise every device listed is considered.\n"
64c4757e 411"\n"
52826846
NB
412" If the --scan option is given, and no devices are listed, then\n"
413" every array listed in the config file is considered for assembly.\n"
e0d19036 414" The identity of candidate devices are determined from the config file.\n"
58380584
N
415" After these arrays are assembled, mdadm will look for other devices\n"
416" that could form further arrays and tries to assemble them. This can\n"
417" be disabled using the 'AUTO' option in the config file.\n"
64c4757e 418"\n"
52826846
NB
419" If the --scan option is given as well as one or more devices, then\n"
420" Those devices are md devices that are to be assembled. Their identity\n"
421" and components are determined from the config file.\n"
64c4757e 422"\n"
b8a8ccf9
NB
423" If mdadm can not find all of the components for an array, it will assemble\n"
424" it but not activate it unless --run or --scan is given. To preserve this\n"
425" behaviour even with --scan, add --no-degraded. Note that \"all of the\n"
426" components\" means as many as were present the last time the array was running\n"
427" as recorded in the superblock. If the array was already degraded, and\n"
428" the missing device is not a new problem, it will still be assembled. It\n"
429" is only newly missing devices that cause the array not to be started.\n"
430"\n"
e0d19036 431"Options that are valid with --assemble (-A) are:\n"
58380584 432" --bitmap= : bitmap file to use with the array\n"
e0d19036
NB
433" --uuid= -u : uuid of array to assemble. Devices which don't\n"
434" have this uuid are excluded\n"
435" --super-minor= -m : minor number to look for in super-block when\n"
436" choosing devices to use.\n"
947fd4dd 437" --name= -N : Array name to look for in super-block.\n"
e0d19036
NB
438" --config= -c : config file\n"
439" --scan -s : scan config file for missing information\n"
440" --run -R : Try to start the array even if not enough devices\n"
441" for a full array are present\n"
442" --force -f : Assemble the array even if some superblocks appear\n"
443" : out-of-date. This involves modifying the superblocks.\n"
cbfbcb0b 444" --update= -U : Update superblock: try '-A --update=?' for option list.\n"
b8a8ccf9 445" --no-degraded : Assemble but do not start degraded arrays.\n"
0ea8f5b1 446" --readonly -o : Mark the array as read-only. No resync will start.\n"
e0d19036
NB
447;
448
449char Help_manage[] =
450"Usage: mdadm arraydevice options component devices...\n"
451"\n"
452"This usage is for managing the component devices within an array.\n"
453"The --manage option is not needed and is assumed if the first argument\n"
454"is a device name or a management option.\n"
58380584 455"The first device listed will be taken to be an md array device, any\n"
e0d19036
NB
456"subsequent devices are (potential) components of that array.\n"
457"\n"
458"Options that are valid with management mode are:\n"
459" --add -a : hotadd subsequent devices to the array\n"
58380584
N
460" --re-add : subsequent devices are re-added if there were\n"
461" : recent members of the array\n"
e0d19036
NB
462" --remove -r : remove subsequent devices, which must not be active\n"
463" --fail -f : mark subsequent devices a faulty\n"
464" --set-faulty : same as --fail\n"
465" --run -R : start a partially built array\n"
5787fa49 466" --stop -S : deactivate array, releasing all resources\n"
e0d19036
NB
467" --readonly -o : mark array as readonly\n"
468" --readwrite -w : mark array as readwrite\n"
469;
470
471char Help_misc[] =
472"Usage: mdadm misc_option devices...\n"
473"\n"
474"This usage is for performing some task on one or more devices, which\n"
475"may be arrays or components, depending on the task.\n"
476"The --misc option is not needed (though it is allowed) and is assumed\n"
477"if the first argument in a misc option.\n"
478"\n"
479"Options that are valid with the miscellaneous mode are:\n"
480" --query -Q : Display general information about how a\n"
481" device relates to the md driver\n"
482" --detail -D : Display details of an array\n"
4cce4069 483" --detail-platform : Display hardware/firmware details\n"
5787fa49 484" --examine -E : Examine superblock on an array component\n"
c82f047c 485" --examine-bitmap -X: Display contents of a bitmap file\n"
e0d19036
NB
486" --zero-superblock : erase the MD superblock from a device.\n"
487" --run -R : start a partially built array\n"
5787fa49 488" --stop -S : deactivate array, releasing all resources\n"
e0d19036
NB
489" --readonly -o : mark array as readonly\n"
490" --readwrite -w : mark array as readwrite\n"
feb716e9 491" --test -t : exit status 0 if ok, 1 if degrade, 2 if dead, 4 if missing\n"
b90c0e9a 492" --wait -W : wait for resync/rebuild/recovery to finish\n"
e0d19036
NB
493;
494
495char Help_monitor[] =
496"Usage: mdadm --monitor options devices\n"
497"\n"
498"This usage causes mdadm to monitor a number of md arrays by periodically\n"
499"polling their status and acting on any changes.\n"
500"If any devices are listed then those devices are monitored, otherwise\n"
501"all devices listed in the config file are monitored.\n"
502"The address for mailing advisories to, and the program to handle\n"
503"each change can be specified in the config file or on the command line.\n"
58380584
N
504"There must be at least one destination for advisories, whether\n"
505"an email address, a program, or --syslog\n"
e0d19036 506"\n"
dd0781e5 507"Options that are valid with the monitor (-F --follow) mode are:\n"
e0d19036
NB
508" --mail= -m : Address to mail alerts of failure to\n"
509" --program= -p : Program to run when an event is detected\n"
510" --alert= : same as --program\n"
237d8790 511" --syslog -y : Report alerts via syslog\n"
9a36a9b7 512" --increment= -r : Report RebuildNN events in the given increment. default=20\n"
e0d19036
NB
513" --delay= -d : seconds of delay between polling state. default=60\n"
514" --config= -c : specify a different config file\n"
515" --scan -s : find mail-address/program in config file\n"
d013a55e 516" --daemonise -f : Fork and continue in child, parent exits\n"
b5e64645 517" --pid-file= -i : In daemon mode write pid to specified file instead of stdout\n"
aa88f531 518" --oneshot -1 : Check for degraded arrays, then exit\n"
98c6faba 519" --test -t : Generate a TestMessage event against each array at startup\n"
e0d19036
NB
520;
521
dd0781e5
NB
522char Help_grow[] =
523"Usage: mdadm --grow device options\n"
524"\n"
525"This usage causes mdadm to attempt to reconfigure a running array.\n"
526"This is only possibly if the kernel being used supports a particular\n"
58380584 527"reconfiguration.\n"
dd0781e5 528"\n"
891d2994 529"Options that are valid with the grow (-G --grow) mode are:\n"
58380584 530" --level= -l : Tell mdadm what level to convert the array to.\n"
00be0b12 531" --layout= -p : For a FAULTY array, set/change the error mode.\n"
58380584 532" : for other arrays, update the layout\n"
dd0781e5
NB
533" --size= -z : Change the active size of devices in an array.\n"
534" : This is useful if all devices have been replaced\n"
0083584d
N
535" : with larger devices. Value is in Kilobytes, or\n"
536" : the special word 'max' meaning 'as large as possible'.\n"
58380584
N
537" --assume-clean : When increasing the --size, this flag will avoid\n"
538" : a resync of the new space\n"
539" --chunk= -c : Change the chunksize of the array\n"
e5669f40 540" --raid-devices= -n : Change the number of active devices in an array.\n"
58380584
N
541" --add= -a : Add listed devices as part of reshape. This is\n"
542" : needed for resizing a RAID0 which cannot have\n"
543" : spares already present.\n"
00be0b12 544" --bitmap= -b : Add or remove a write-intent bitmap.\n"
58380584 545" --backup-file= file : A file on a different device to store data for a\n"
e5669f40 546" : short time while increasing raid-devices on a\n"
58380584
N
547" : RAID4/5/6 array. Also needed throughout a reshape\n"
548" : when changing parameters other than raid-devices\n"
84e11361
N
549" --array-size= -Z : Change visible size of array. This does not change\n"
550" : any data on the device, and is not stable across restarts.\n"
40c9a66a 551" --data-offset= : Location on device to move start of data to.\n"
dd0781e5 552;
e0d19036 553
8382f19b 554char Help_incr[] =
29ba4804 555"Usage: mdadm --incremental [-Rqrsf] device\n"
8382f19b
NB
556"\n"
557"This usage allows for incremental assembly of md arrays. Devices can be\n"
558"added one at a time as they are discovered. Once an array has all expected\n"
559"devices, it will be started.\n"
560"\n"
29ba4804
N
561"Optionally, the process can be reversed by using the fail option.\n"
562"When fail mode is invoked, mdadm will see if the device belongs to an array\n"
563"and then both fail (if needed) and remove the device from that array.\n"
564"\n"
565"Options that are valid with incremental assembly (-I --incremental) are:\n"
566" --run -R : Run arrays as soon as a minimal number of devices are\n"
7e6140e6
N
567" : present rather than waiting for all expected.\n"
568" --quiet -q : Don't print any information messages, just errors.\n"
569" --rebuild-map -r : Rebuild the 'map' file that mdadm uses for tracking\n"
570" : partial arrays.\n"
571" --scan -s : Use with -R to start any arrays that have the minimal\n"
572" : required number of devices, but are not yet started.\n"
58380584
N
573" --fail -f : First fail (if needed) and then remove device from\n"
574" : any array that it is a member of.\n"
8382f19b 575;
e0d19036
NB
576
577char Help_config[] =
578"The /etc/mdadm.conf config file:\n\n"
579" The config file contains, apart from blank lines and comment lines that\n"
58380584
N
580" start with a hash(#), array lines, device lines, and various\n"
581" configuration lines.\n"
582" Each line is constructed of a number of space separated words, and can\n"
583" be continued on subsequent physical lines by indenting those lines.\n"
e0d19036
NB
584"\n"
585" A device line starts with the word 'device' and then has a number of words\n"
586" which identify devices. These words should be names of devices in the\n"
587" filesystem, and can contain wildcards. There can be multiple words or each\n"
588" device line, and multiple device lines. All devices so listed are checked\n"
589" for relevant super blocks when assembling arrays.\n"
590"\n"
591" An array line start with the word 'array'. This is followed by the name of\n"
592" the array device in the filesystem, e.g. '/dev/md2'. Subsequent words\n"
593" describe the identity of the array, used to recognise devices to include in the\n"
594" array. The identity can be given as a UUID with a word starting 'uuid=', or\n"
595" as a minor-number stored in the superblock using 'super-minor=', or as a list\n"
596" of devices. This is given as a comma separated list of names, possibly\n"
5787fa49 597" containing wildcards, preceded by 'devices='. If multiple critea are given,\n"
e0d19036
NB
598" than a device must match all of them to be considered.\n"
599"\n"
58380584
N
600" Other configuration lines include:\n"
601" mailaddr, mailfrom, program used for --monitor mode\n"
602" create, auto used when creating device names in /dev\n"
603" homehost, policy, part-policy used to guide policy in various\n"
604" situations\n"
64c4757e
NB
605"\n"
606;
682c7051 607
5187a385
N
608char *mode_help[mode_count] = {
609 [0] = Help,
610 [ASSEMBLE] = Help_assemble,
611 [BUILD] = Help_build,
612 [CREATE] = Help_create,
613 [MANAGE] = Help_manage,
614 [MISC] = Help_misc,
615 [MONITOR] = Help_monitor,
616 [GROW] = Help_grow,
617 [INCREMENTAL] = Help_incr,
618};