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Assemble(): don't dup_super() before we need it.
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64c4757e 1/*
9a9dab36 2 * mdadm - manage Linux "md" devices aka RAID arrays.
64c4757e 3 *
a31c140f 4 * Copyright (C) 2001-2010 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
ef799cdd 27char Version[] = Name " - v3.2.2 - 17th June 2011\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 *
9a9dab36 35 * mdadm is a single program that can be used to control Linux md devices.
64c4757e
NB
36 * It is intended to provide all the functionality of the mdtools and
37 * raidtools but with a very different interface.
9a9dab36 38 * mdadm can perform all functions without a configuration file.
64c4757e
NB
39 * There is the option of using a configuration file, but not in the same
40 * way that raidtools uses one
41 * raidtools uses a configuration file to describe how to create a RAID
42 * array, and also uses this file partially to start a previously
43 * created RAID array. Further, raidtools requires the configuration
44 * file for such things as stopping a raid array which needs to know
45 * nothing about the array.
46 *
9a9dab36 47 * The configuration file that can be used by mdadm lists two
64c4757e
NB
48 * different things:
49 * 1/ a mapping from uuid to md device to identify which arrays are
50 * expect and what names (numbers) they should be given
51 * 2/ a list of devices that should be scanned for md sub-devices
52 *
53 *
54 */
55
56/*
dd0781e5 57 * mdadm has 7 major modes of operation:
64c4757e 58 * 1/ Create
5787fa49 59 * This mode is used to create a new array with a superblock
64c4757e
NB
60 * It can progress in several step create-add-add-run
61 * or it can all happen with one command
62 * 2/ Assemble
63 * This mode is used to assemble the parts of a previously created
64 * array into an active array. Components can be explicitly given
9a9dab36 65 * or can be searched for. mdadm (optionally) check that the components
5787fa49 66 * do form a bona-fide array, and can, on request, fiddle superblock
64c4757e
NB
67 * version numbers so as to assemble a faulty array.
68 * 3/ Build
69 * This is for building legacy arrays without superblocks
70 * 4/ Manage
e0d19036
NB
71 * This is for doing something to one or more devices
72 * in an array, such as add,remove,fail.
73 * run/stop/readonly/readwrite are also available
74 * 5/ Misc
75 * This is for doing things to individual devices.
76 * They might be parts of an array so
77 * zero-superblock, examine might be appropriate
78 * They might be md arrays so
79 * run,stop,rw,ro,detail might be appropriate
80 * Also query will treat it as either
81 * 6/ Monitor
82 * This mode never exits but just monitors arrays and reports changes.
dd0781e5
NB
83 * 7/ Grow
84 * This mode allows for changing of key attributes of a raid array, such
85 * as size, number of devices, and possibly even layout.
86 * At the time if writing, there is only minimal support.
64c4757e
NB
87 */
88
866f509f 89char short_options[]="-ABCDEFGIQhVXYWZ:vqbc:i:l:p:m:n:x:u:c:d:z:U:N:sarfRSow1tye:";
024768c4 90char short_bitmap_options[]=
866f509f 91 "-ABCDEFGIQhVXYWZ:vqb:c:i:l:p:m:n:x:u:c:d:z:U:N:sarfRSow1tye:";
8382f19b 92char short_bitmap_auto_options[]=
866f509f 93 "-ABCDEFGIQhVXYWZ:vqb:c:i:l:p:m:n:x:u:c:d:z:U:N:sa:rfRSow1tye:";
773135f5 94
64c4757e 95struct option long_options[] = {
1c7a808c
N
96 {"manage", 0, 0, ManageOpt},
97 {"misc", 0, 0, MiscOpt},
64c4757e
NB
98 {"assemble", 0, 0, 'A'},
99 {"build", 0, 0, 'B'},
100 {"create", 0, 0, 'C'},
101 {"detail", 0, 0, 'D'},
102 {"examine", 0, 0, 'E'},
52826846 103 {"follow", 0, 0, 'F'},
dd0781e5 104 {"grow", 0, 0, 'G'},
8382f19b 105 {"incremental",0,0, 'I'},
e0d19036
NB
106 {"zero-superblock", 0, 0, 'K'}, /* deliberately no a short_option */
107 {"query", 0, 0, 'Q'},
c82f047c 108 {"examine-bitmap", 0, 0, 'X'},
1f48664b 109 {"auto-detect", 0, 0, AutoDetect},
4cce4069 110 {"detail-platform", 0, 0, DetailPlatform},
33414a01 111 {"kill-subarray", 1, 0, KillSubarray},
aa534678 112 {"update-subarray", 1, 0, UpdateSubarray},
20b60dcd 113 {"udev-rules", 2, 0, UdevRules},
52826846
NB
114
115 /* synonyms */
116 {"monitor", 0, 0, 'F'},
aba69144 117
64c4757e
NB
118 /* after those will normally come the name of the md device */
119 {"help", 0, 0, 'h'},
1c7a808c 120 {"help-options",0,0, HelpOptions},
64c4757e
NB
121 {"version", 0, 0, 'V'},
122 {"verbose", 0, 0, 'v'},
dab6685f 123 {"quiet", 0, 0, 'q'},
64c4757e
NB
124
125 /* For create or build: */
1c7a808c
N
126 {"chunk", 1, 0, ChunkSize},
127 {"rounding", 1, 0, ChunkSize}, /* for linear, chunk is really a
128 * rounding number */
98c6faba 129 {"level", 1, 0, 'l'}, /* 0,1,4,5,6,linear */
1c7a808c
N
130 {"parity", 1, 0, Layout}, /* {left,right}-{a,}symmetric */
131 {"layout", 1, 0, Layout},
64c4757e 132 {"raid-disks",1, 0, 'n'},
b83d95f3 133 {"raid-devices",1, 0, 'n'},
64c4757e 134 {"spare-disks",1,0, 'x'},
b83d95f3 135 {"spare-devices",1,0, 'x'},
dd0781e5 136 {"size", 1, 0, 'z'},
1c7a808c 137 {"auto", 1, 0, Auto}, /* also for --assemble */
997aed5d 138 {"assume-clean",0,0, AssumeClean },
f9ce90ba 139 {"metadata", 1, 0, 'e'}, /* superblock format */
1c7a808c 140 {"bitmap", 1, 0, Bitmap},
997aed5d
NB
141 {"bitmap-chunk", 1, 0, BitmapChunk},
142 {"write-behind", 2, 0, WriteBehind},
1c7a808c 143 {"write-mostly",0, 0, WriteMostly},
997aed5d
NB
144 {"re-add", 0, 0, ReAdd},
145 {"homehost", 1, 0, HomeHost},
38098016 146 {"symlinks", 1, 0, Symlinks},
64c4757e
NB
147
148 /* For assemble */
149 {"uuid", 1, 0, 'u'},
1c7a808c 150 {"super-minor",1,0, SuperMinor},
947fd4dd 151 {"name", 1, 0, 'N'},
1c7a808c 152 {"config", 1, 0, ConfigFile},
64c4757e 153 {"scan", 0, 0, 's'},
1c7a808c 154 {"force", 0, 0, Force},
5787fa49 155 {"update", 1, 0, 'U'},
b76b30e0 156 {"freeze-reshape", 0, 0, FreezeReshape},
dfd4d8ee 157
64c4757e 158 /* Management */
1c7a808c
N
159 {"add", 0, 0, Add},
160 {"remove", 0, 0, Remove},
161 {"fail", 0, 0, Fail},
162 {"set-faulty",0, 0, Fail},
64c4757e
NB
163 {"run", 0, 0, 'R'},
164 {"stop", 0, 0, 'S'},
165 {"readonly", 0, 0, 'o'},
166 {"readwrite", 0, 0, 'w'},
997aed5d 167 {"no-degraded",0,0, NoDegraded },
1c7a808c 168 {"wait", 0, 0, WaitOpt},
1770662b 169 {"wait-clean", 0, 0, Waitclean },
52826846 170
cd29a5c8 171 /* For Detail/Examine */
1c7a808c 172 {"brief", 0, 0, Brief},
54bad364 173 {"export", 0, 0, 'Y'},
997aed5d 174 {"sparc2.2", 0, 0, Sparc22},
feb716e9 175 {"test", 0, 0, 't'},
cd29a5c8 176
52826846 177 /* For Follow/monitor */
1c7a808c
N
178 {"mail", 1, 0, EMail},
179 {"program", 1, 0, ProgramOpt},
180 {"alert", 1, 0, ProgramOpt},
181 {"increment", 1, 0, Increment},
52826846 182 {"delay", 1, 0, 'd'},
1c7a808c
N
183 {"daemonise", 0, 0, Fork},
184 {"daemonize", 0, 0, Fork},
aa88f531 185 {"oneshot", 0, 0, '1'},
b5e64645 186 {"pid-file", 1, 0, 'i'},
90cf1ddd 187 {"syslog", 0, 0, 'y'},
edde9560
AC
188 {"no-sharing", 0, 0, NoSharing},
189
06b0d786 190 /* For Grow */
997aed5d 191 {"backup-file", 1,0, BackupFile},
87f26d14 192 {"invalid-backup",0,0,InvalidBackup},
84e11361 193 {"array-size", 1, 0, 'Z'},
2dddadb0 194 {"continue", 0, 0, Continue},
8382f19b
NB
195
196 /* For Incremental */
1c7a808c 197 {"rebuild-map", 0, 0, RebuildMapOpt},
950bc344
PC
198 {"path", 1, 0, IncrementalPath},
199
64c4757e
NB
200 {0, 0, 0, 0}
201};
202
203char Usage[] =
9a9dab36 204"Usage: mdadm --help\n"
64c4757e
NB
205" for help\n"
206;
207
208char Help[] =
e5a5d81e
NB
209"mdadm is used for building, managing, and monitoring\n"
210"Linux md devices (aka RAID arrays)\n"
9a9dab36 211"Usage: mdadm --create device options...\n"
e5a5d81e 212" Create a new array from unused devices.\n"
9a9dab36 213" mdadm --assemble device options...\n"
e968ba60 214" Assemble a previously created array.\n"
9a9dab36 215" mdadm --build device options...\n"
e5a5d81e 216" Create or assemble an array without metadata.\n"
e0d19036 217" mdadm --manage device options...\n"
e968ba60 218" make changes to an existing array.\n"
e0d19036 219" mdadm --misc options... devices\n"
e968ba60 220" report on or modify various md related devices.\n"
8382f19b
NB
221" mdadm --grow options device\n"
222" resize/reshape an active array\n"
223" mdadm --incremental device\n"
29ba4804 224" add/remove a device to/from an array as appropriate\n"
e0d19036 225" mdadm --monitor options...\n"
e968ba60 226" Monitor one or more array for significant changes.\n"
9a9dab36 227" mdadm device options...\n"
e968ba60 228" Shorthand for --manage.\n"
e5a5d81e
NB
229"Any parameter that does not start with '-' is treated as a device name\n"
230"or, for --examine-bitmap, a file name.\n"
231"The first such name is often the name of an md device. Subsequent\n"
232"names are often names of component devices.\n"
233"\n"
56eedc1a 234" For detailed help on the above major modes use --help after the mode\n"
e0d19036 235" e.g.\n"
9a9dab36 236" mdadm --assemble --help\n"
56eedc1a
NB
237" For general help on options use\n"
238" mdadm --help-options\n"
239;
240
241char OptionHelp[] =
64c4757e 242"Any parameter that does not start with '-' is treated as a device name\n"
c82f047c 243"or, for --examine-bitmap, a file name.\n"
e0d19036 244"The first such name is often the name of an md device. Subsequent\n"
e5a5d81e 245"names are often names of component devices.\n"
52826846 246"\n"
e0d19036 247"Some common options are:\n"
56eedc1a 248" --help -h : General help message or, after above option,\n"
64c4757e 249" mode specific help message\n"
56eedc1a 250" --help-options : This help message\n"
9a9dab36 251" --version -V : Print version information for mdadm\n"
64c4757e 252" --verbose -v : Be more verbose about what is happening\n"
dab6685f 253" --quiet -q : Don't print un-necessary messages\n"
e0d19036 254" --brief -b : Be less verbose, more brief\n"
54bad364
KS
255" --export -Y : With --detail, use key=value format for easy\n"
256" import into environment\n"
e0d19036
NB
257" --force -f : Override normal checks and be more forceful\n"
258"\n"
259" --assemble -A : Assemble an array\n"
e5a5d81e 260" --build -B : Build an array without metadata\n"
e0d19036
NB
261" --create -C : Create a new array\n"
262" --detail -D : Display details of an array\n"
5787fa49 263" --examine -E : Examine superblock on an array component\n"
c82f047c 264" --examine-bitmap -X: Display the detail of a bitmap file\n"
e0d19036 265" --monitor -F : monitor (follow) some arrays\n"
8382f19b 266" --grow -G : resize/ reshape and array\n"
29ba4804 267" --incremental -I : add/remove a single device to/from an array as appropriate\n"
e0d19036
NB
268" --query -Q : Display general information about how a\n"
269" device relates to the md driver\n"
1f48664b 270" --auto-detect : Start arrays auto-detected by the kernel\n"
e0d19036
NB
271;
272/*
64c4757e
NB
273"\n"
274" For create or build:\n"
c82f047c 275" --bitmap= -b : File to store bitmap in - may pre-exist for --build\n"
64c4757e 276" --chunk= -c : chunk size of kibibytes\n"
5787fa49 277" --rounding= : rounding factor for linear array (==chunk size)\n"
98c6faba
NB
278" --level= -l : raid level: 0,1,4,5,6,linear,mp. 0 or linear for build\n"
279" --parity= -p : raid5/6 parity algorithm: {left,right}-{,a}symmetric\n"
64c4757e 280" --layout= : same as --parity\n"
b83d95f3
NB
281" --raid-devices= -n : number of active devices in array\n"
282" --spare-devices= -x: number of spares (eXtras) devices in initial array\n"
e5329c37 283" --size= -z : Size (in K) of each drive in RAID1/4/5/6/10 - optional\n"
52826846
NB
284" --force -f : Honour devices as listed on command line. Don't\n"
285" : insert a missing drive for RAID5.\n"
dd0781e5 286" --assume-clean : Assume the array is already in-sync. This is dangerous.\n"
c82f047c
NB
287" --bitmap-chunk= : chunksize of bitmap in bitmap file (Kilobytes)\n"
288" --delay= -d : seconds between bitmap updates\n"
dfd4d8ee 289" --write-behind= : number of simultaneous write-behind requests to allow (requires bitmap)\n"
947fd4dd 290" --name= -N : Textual name for array - max 32 characters\n"
64c4757e
NB
291"\n"
292" For assemble:\n"
c82f047c 293" --bitmap= -b : File to find bitmap information in\n"
64c4757e
NB
294" --uuid= -u : uuid of array to assemble. Devices which don't\n"
295" have this uuid are excluded\n"
52826846
NB
296" --super-minor= -m : minor number to look for in super-block when\n"
297" choosing devices to use.\n"
947fd4dd 298" --name= -N : Array name to look for in super-block.\n"
64c4757e
NB
299" --config= -c : config file\n"
300" --scan -s : scan config file for missing information\n"
301" --force -f : Assemble the array even if some superblocks appear out-of-date\n"
cbfbcb0b 302" --update= -U : Update superblock: try '-A --update=?' for list of options.\n"
b8a8ccf9 303" --no-degraded : Do not start any degraded arrays - default unless --scan.\n"
64c4757e 304"\n"
cd29a5c8
NB
305" For detail or examine:\n"
306" --brief -b : Just print device name and UUID\n"
307"\n"
52826846
NB
308" For follow/monitor:\n"
309" --mail= -m : Address to mail alerts of failure to\n"
310" --program= -p : Program to run when an event is detected\n"
311" --alert= : same as --program\n"
312" --delay= -d : seconds of delay between polling state. default=60\n"
313"\n"
64c4757e
NB
314" General management:\n"
315" --add -a : add, or hotadd subsequent devices\n"
316" --remove -r : remove subsequent devices\n"
317" --fail -f : mark subsequent devices a faulty\n"
318" --set-faulty : same as --fail\n"
319" --run -R : start a partially built array\n"
5787fa49 320" --stop -S : deactivate array, releasing all resources\n"
64c4757e
NB
321" --readonly -o : mark array as readonly\n"
322" --readwrite -w : mark array as readwrite\n"
9a9dab36 323" --zero-superblock : erase the MD superblock from a device.\n"
b90c0e9a 324" --wait -W : wait for recovery/resync/reshape to finish.\n"
64c4757e 325;
e0d19036 326*/
64c4757e
NB
327
328char Help_create[] =
b83d95f3 329"Usage: mdadm --create device -chunk=X --level=Y --raid-devices=Z devices\n"
64c4757e 330"\n"
aa88f531
NB
331" This usage will initialise a new md array, associate some\n"
332" devices with it, and activate the array. In order to create an\n"
333" array with some devices missing, use the special word 'missing' in\n"
334" place of the relevant device name.\n"
64c4757e 335"\n"
aa88f531 336" Before devices are added, they are checked to see if they already contain\n"
e0d19036 337" raid superblocks or filesystems. They are also checked to see if\n"
64c4757e 338" the variance in device size exceeds 1%.\n"
aa88f531
NB
339" If any discrepancy is found, the user will be prompted for confirmation\n"
340" before the array is created. The presence of a '--run' can override this\n"
64c4757e
NB
341" caution.\n"
342"\n"
e0d19036
NB
343" If the --size option is given then only that many kilobytes of each\n"
344" device is used, no matter how big each device is.\n"
682c7051 345" If no --size is given, the apparent size of the smallest drive given\n"
e0d19036
NB
346" is used for raid level 1 and greater, and the full device is used for\n"
347" other levels.\n"
682c7051 348"\n"
e0d19036 349" Options that are valid with --create (-C) are:\n"
c82f047c 350" --bitmap= : Create a bitmap for the array with the given filename\n"
e0d19036 351" --chunk= -c : chunk size of kibibytes\n"
5787fa49 352" --rounding= : rounding factor for linear array (==chunk size)\n"
98c6faba
NB
353" --level= -l : raid level: 0,1,4,5,6,linear,multipath and synonyms\n"
354" --parity= -p : raid5/6 parity algorithm: {left,right}-{,a}symmetric\n"
e0d19036 355" --layout= : same as --parity\n"
b83d95f3
NB
356" --raid-devices= -n : number of active devices in array\n"
357" --spare-devices= -x: number of spares (eXtras) devices in initial array\n"
e5329c37 358" --size= -z : Size (in K) of each drive in RAID1/4/5/6/10 - optional\n"
e0d19036
NB
359" --force -f : Honour devices as listed on command line. Don't\n"
360" : insert a missing drive for RAID5.\n"
aa88f531 361" --run -R : insist of running the array even if not all\n"
e0d19036 362" : devices are present or some look odd.\n"
aa88f531 363" --readonly -o : start the array readonly - not supported yet.\n"
947fd4dd 364" --name= -N : Textual name for array - max 32 characters\n"
c82f047c
NB
365" --bitmap-chunk= : bitmap chunksize in Kilobytes.\n"
366" --delay= -d : bitmap update delay in seconds.\n"
64c4757e
NB
367"\n"
368;
369
370char Help_build[] =
b83d95f3 371"Usage: mdadm --build device -chunk=X --level=Y --raid-devices=Z devices\n"
64c4757e
NB
372"\n"
373" This usage is similar to --create. The difference is that it creates\n"
e0d19036 374" a legacy array without a superblock. With these arrays there is no\n"
64c4757e
NB
375" different between initially creating the array and subsequently\n"
376" assembling the array, except that hopefully there is useful data\n"
377" there in the second case.\n"
378"\n"
e0d19036 379" The level may only be 0, raid0, or linear.\n"
64c4757e 380" All devices must be listed and the array will be started once complete.\n"
e0d19036 381" Options that are valid with --build (-B) are:\n"
c82f047c 382" --bitmap= : file to store/find bitmap information in.\n"
e0d19036 383" --chunk= -c : chunk size of kibibytes\n"
5787fa49 384" --rounding= : rounding factor for linear array (==chunk size)\n"
e0d19036 385" --level= -l : 0, raid0, or linear\n"
c82f047c
NB
386" --raid-devices= -n : number of active devices in array\n"
387" --bitmap-chunk= : bitmap chunksize in Kilobytes.\n"
388" --delay= -d : bitmap update delay in seconds.\n"
64c4757e
NB
389;
390
391char Help_assemble[] =
9a9dab36
NB
392"Usage: mdadm --assemble device options...\n"
393" mdadm --assemble --scan options...\n"
64c4757e
NB
394"\n"
395"This usage assembles one or more raid arrays from pre-existing\n"
396"components.\n"
e0d19036 397"For each array, mdadm needs to know the md device, the identity of\n"
52826846
NB
398"the array, and a number of sub devices. These can be found in a number\n"
399"of ways.\n"
400"\n"
401"The md device is either given on the command line or is found listed\n"
402"in the config file. The array identity is determined either from the\n"
e0d19036 403"--uuid or --super-minor commandline arguments, from the config file,\n"
52826846 404"or from the first component device on the command line.\n"
64c4757e 405"\n"
52826846
NB
406"The different combinations of these are as follows:\n"
407" If the --scan option is not given, then only devices and identities\n"
408" listed on the command line are considered.\n"
e0d19036 409" The first device will be the array device, and the remainder will be\n"
52826846
NB
410" examined when looking for components.\n"
411" If an explicit identity is given with --uuid or --super-minor, then\n"
e0d19036 412" only devices with a superblock which matches that identity is considered,\n"
52826846 413" otherwise every device listed is considered.\n"
64c4757e 414"\n"
52826846
NB
415" If the --scan option is given, and no devices are listed, then\n"
416" every array listed in the config file is considered for assembly.\n"
e0d19036 417" The identity of candidate devices are determined from 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"
c82f047c 432" --bitmap= : bitmap file to use wit 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"
e0d19036
NB
446;
447
448char Help_manage[] =
449"Usage: mdadm arraydevice options component devices...\n"
450"\n"
451"This usage is for managing the component devices within an array.\n"
452"The --manage option is not needed and is assumed if the first argument\n"
453"is a device name or a management option.\n"
454"The first device listed will be taken to be an md array device, and\n"
455"subsequent devices are (potential) components of that array.\n"
456"\n"
457"Options that are valid with management mode are:\n"
458" --add -a : hotadd subsequent devices to the array\n"
459" --remove -r : remove subsequent devices, which must not be active\n"
460" --fail -f : mark subsequent devices a faulty\n"
461" --set-faulty : same as --fail\n"
462" --run -R : start a partially built array\n"
5787fa49 463" --stop -S : deactivate array, releasing all resources\n"
e0d19036
NB
464" --readonly -o : mark array as readonly\n"
465" --readwrite -w : mark array as readwrite\n"
466;
467
468char Help_misc[] =
469"Usage: mdadm misc_option devices...\n"
470"\n"
471"This usage is for performing some task on one or more devices, which\n"
472"may be arrays or components, depending on the task.\n"
473"The --misc option is not needed (though it is allowed) and is assumed\n"
474"if the first argument in a misc option.\n"
475"\n"
476"Options that are valid with the miscellaneous mode are:\n"
477" --query -Q : Display general information about how a\n"
478" device relates to the md driver\n"
479" --detail -D : Display details of an array\n"
4cce4069 480" --detail-platform : Display hardware/firmware details\n"
5787fa49 481" --examine -E : Examine superblock on an array component\n"
c82f047c 482" --examine-bitmap -X: Display contents of a bitmap file\n"
e0d19036
NB
483" --zero-superblock : erase the MD superblock from a device.\n"
484" --run -R : start a partially built array\n"
5787fa49 485" --stop -S : deactivate array, releasing all resources\n"
e0d19036
NB
486" --readonly -o : mark array as readonly\n"
487" --readwrite -w : mark array as readwrite\n"
feb716e9 488" --test -t : exit status 0 if ok, 1 if degrade, 2 if dead, 4 if missing\n"
b90c0e9a 489" --wait -W : wait for resync/rebuild/recovery to finish\n"
e0d19036
NB
490;
491
492char Help_monitor[] =
493"Usage: mdadm --monitor options devices\n"
494"\n"
495"This usage causes mdadm to monitor a number of md arrays by periodically\n"
496"polling their status and acting on any changes.\n"
497"If any devices are listed then those devices are monitored, otherwise\n"
498"all devices listed in the config file are monitored.\n"
499"The address for mailing advisories to, and the program to handle\n"
500"each change can be specified in the config file or on the command line.\n"
501"If no mail address or program are specified, then mdadm reports all\n"
502"state changes to stdout.\n"
503"\n"
dd0781e5 504"Options that are valid with the monitor (-F --follow) mode are:\n"
e0d19036
NB
505" --mail= -m : Address to mail alerts of failure to\n"
506" --program= -p : Program to run when an event is detected\n"
507" --alert= : same as --program\n"
237d8790 508" --syslog -y : Report alerts via syslog\n"
9a36a9b7 509" --increment= -r : Report RebuildNN events in the given increment. default=20\n"
e0d19036
NB
510" --delay= -d : seconds of delay between polling state. default=60\n"
511" --config= -c : specify a different config file\n"
512" --scan -s : find mail-address/program in config file\n"
d013a55e 513" --daemonise -f : Fork and continue in child, parent exits\n"
b5e64645 514" --pid-file= -i : In daemon mode write pid to specified file instead of stdout\n"
aa88f531 515" --oneshot -1 : Check for degraded arrays, then exit\n"
98c6faba 516" --test -t : Generate a TestMessage event against each array at startup\n"
e0d19036
NB
517;
518
dd0781e5
NB
519char Help_grow[] =
520"Usage: mdadm --grow device options\n"
521"\n"
522"This usage causes mdadm to attempt to reconfigure a running array.\n"
523"This is only possibly if the kernel being used supports a particular\n"
00be0b12
NB
524"reconfiguration. This version supports changing the number of\n"
525"devices in a RAID1/5/6, changing the active size of all devices in\n"
526"a RAID1/4/5/6, adding or removing a write-intent bitmap, and changing\n"
527"the error mode for a 'FAULTY' array.\n"
dd0781e5 528"\n"
891d2994 529"Options that are valid with the grow (-G --grow) mode are:\n"
00be0b12
NB
530" --level= -l : Tell mdadm what level the array is so that it can\n"
531" : interpret '--layout' properly.\n"
532" --layout= -p : For a FAULTY array, set/change the error mode.\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"
e5669f40 537" --raid-devices= -n : Change the number of active devices in an array.\n"
00be0b12 538" --bitmap= -b : Add or remove a write-intent bitmap.\n"
e5669f40
N
539" --backup-file= file : A file on a differt device to store data for a\n"
540" : short time while increasing raid-devices on a\n"
541" : RAID4/5/6 array. Not needed when a spare is present.\n"
84e11361
N
542" --array-size= -Z : Change visible size of array. This does not change\n"
543" : any data on the device, and is not stable across restarts.\n"
dd0781e5 544;
e0d19036 545
8382f19b 546char Help_incr[] =
29ba4804 547"Usage: mdadm --incremental [-Rqrsf] device\n"
8382f19b
NB
548"\n"
549"This usage allows for incremental assembly of md arrays. Devices can be\n"
550"added one at a time as they are discovered. Once an array has all expected\n"
551"devices, it will be started.\n"
552"\n"
29ba4804
N
553"Optionally, the process can be reversed by using the fail option.\n"
554"When fail mode is invoked, mdadm will see if the device belongs to an array\n"
555"and then both fail (if needed) and remove the device from that array.\n"
556"\n"
557"Options that are valid with incremental assembly (-I --incremental) are:\n"
558" --run -R : Run arrays as soon as a minimal number of devices are\n"
7e6140e6
N
559" : present rather than waiting for all expected.\n"
560" --quiet -q : Don't print any information messages, just errors.\n"
561" --rebuild-map -r : Rebuild the 'map' file that mdadm uses for tracking\n"
562" : partial arrays.\n"
563" --scan -s : Use with -R to start any arrays that have the minimal\n"
564" : required number of devices, but are not yet started.\n"
29ba4804
N
565" --fail -f : First fail (if needed) and then remove device from\n"
566" : any array that it is a member of.\n"
8382f19b 567;
e0d19036
NB
568
569char Help_config[] =
570"The /etc/mdadm.conf config file:\n\n"
571" The config file contains, apart from blank lines and comment lines that\n"
572" start with a hash(#), four sorts of configuration lines: array lines, \n"
573" device lines, mailaddr lines and program lines.\n"
574" Each configuration line is constructed of a number of space separated\n"
575" words, and can be continued on subsequent physical lines by indenting\n"
576" those lines.\n"
577"\n"
578" A device line starts with the word 'device' and then has a number of words\n"
579" which identify devices. These words should be names of devices in the\n"
580" filesystem, and can contain wildcards. There can be multiple words or each\n"
581" device line, and multiple device lines. All devices so listed are checked\n"
582" for relevant super blocks when assembling arrays.\n"
583"\n"
584" An array line start with the word 'array'. This is followed by the name of\n"
585" the array device in the filesystem, e.g. '/dev/md2'. Subsequent words\n"
586" describe the identity of the array, used to recognise devices to include in the\n"
587" array. The identity can be given as a UUID with a word starting 'uuid=', or\n"
588" as a minor-number stored in the superblock using 'super-minor=', or as a list\n"
589" of devices. This is given as a comma separated list of names, possibly\n"
5787fa49 590" containing wildcards, preceded by 'devices='. If multiple critea are given,\n"
e0d19036
NB
591" than a device must match all of them to be considered.\n"
592"\n"
593" A mailaddr line starts with the word 'mailaddr' and should contain exactly\n"
594" one Email address. 'mdadm --monitor --scan' will send alerts of failed drives\n"
595" to this Email address."
596"\n"
597" A program line starts with the word 'program' and should contain exactly\n"
598" one program name. 'mdadm --monitor --scan' will run this program when any\n"
599" event is detected.\n"
64c4757e
NB
600"\n"
601;
682c7051 602