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Makefile: add EXTRAVERSION support
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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
20e8fe52 31#define VERSION "4.1"
b379508e
N
32#endif
33#ifndef VERS_DATE
20e8fe52 34#define VERS_DATE "2018-10-01"
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
5308f117 84char short_options[]="-ABCDEFGIQhVXYWZ:vqbc:i:l:p:m:n:x:u:c:d:z:U:N:sarfRSow1tye:k:";
024768c4 85char short_bitmap_options[]=
5308f117 86 "-ABCDEFGIQhVXYWZ:vqb:c:i:l:p:m:n:x:u:c:d:z:U:N:sarfRSow1tye:k:";
8382f19b 87char short_bitmap_auto_options[]=
5308f117 88 "-ABCDEFGIQhVXYWZ:vqb:c:i:l:p:m:n:x:u:c:d:z:U:N:sa:rfRSow1tye:k:";
773135f5 89
64c4757e 90struct option long_options[] = {
1c7a808c
N
91 {"manage", 0, 0, ManageOpt},
92 {"misc", 0, 0, MiscOpt},
64c4757e
NB
93 {"assemble", 0, 0, 'A'},
94 {"build", 0, 0, 'B'},
95 {"create", 0, 0, 'C'},
96 {"detail", 0, 0, 'D'},
97 {"examine", 0, 0, 'E'},
52826846 98 {"follow", 0, 0, 'F'},
dd0781e5 99 {"grow", 0, 0, 'G'},
8382f19b 100 {"incremental",0,0, 'I'},
f7d3febc 101 {"zero-superblock", 0, 0, KillOpt}, /* deliberately not a short_option */
e0d19036 102 {"query", 0, 0, 'Q'},
c82f047c 103 {"examine-bitmap", 0, 0, 'X'},
1f48664b 104 {"auto-detect", 0, 0, AutoDetect},
4cce4069 105 {"detail-platform", 0, 0, DetailPlatform},
33414a01 106 {"kill-subarray", 1, 0, KillSubarray},
aa534678 107 {"update-subarray", 1, 0, UpdateSubarray},
20b60dcd 108 {"udev-rules", 2, 0, UdevRules},
08ca2adf 109 {"offroot", 0, 0, OffRootOpt},
6d388a88 110 {"examine-badblocks", 0, 0, ExamineBB},
52826846 111
74db60b0
N
112 {"dump", 1, 0, Dump},
113 {"restore", 1, 0, Restore},
114
52826846
NB
115 /* synonyms */
116 {"monitor", 0, 0, 'F'},
aba69144 117
64c4757e 118 /* after those will normally come the name of the md device */
58380584 119
64c4757e 120 {"help", 0, 0, 'h'},
1c7a808c 121 {"help-options",0,0, HelpOptions},
64c4757e
NB
122 {"version", 0, 0, 'V'},
123 {"verbose", 0, 0, 'v'},
dab6685f 124 {"quiet", 0, 0, 'q'},
64c4757e
NB
125
126 /* For create or build: */
1c7a808c
N
127 {"chunk", 1, 0, ChunkSize},
128 {"rounding", 1, 0, ChunkSize}, /* for linear, chunk is really a
129 * rounding number */
98c6faba 130 {"level", 1, 0, 'l'}, /* 0,1,4,5,6,linear */
1c7a808c
N
131 {"parity", 1, 0, Layout}, /* {left,right}-{a,}symmetric */
132 {"layout", 1, 0, Layout},
64c4757e 133 {"raid-disks",1, 0, 'n'},
b83d95f3 134 {"raid-devices",1, 0, 'n'},
64c4757e 135 {"spare-disks",1,0, 'x'},
b83d95f3 136 {"spare-devices",1,0, 'x'},
dd0781e5 137 {"size", 1, 0, 'z'},
1c7a808c 138 {"auto", 1, 0, Auto}, /* also for --assemble */
997aed5d 139 {"assume-clean",0,0, AssumeClean },
f9ce90ba 140 {"metadata", 1, 0, 'e'}, /* superblock format */
1c7a808c 141 {"bitmap", 1, 0, Bitmap},
997aed5d
NB
142 {"bitmap-chunk", 1, 0, BitmapChunk},
143 {"write-behind", 2, 0, WriteBehind},
1c7a808c 144 {"write-mostly",0, 0, WriteMostly},
71574efb
N
145 {"failfast", 0, 0, FailFast},
146 {"nofailfast",0, 0, NoFailFast},
997aed5d
NB
147 {"re-add", 0, 0, ReAdd},
148 {"homehost", 1, 0, HomeHost},
38098016 149 {"symlinks", 1, 0, Symlinks},
40c9a66a 150 {"data-offset",1, 0, DataOffset},
7e6e839a 151 {"nodes",1, 0, Nodes}, /* also for --assemble */
7716570e 152 {"home-cluster",1, 0, ClusterName},
cc1799c3 153 {"write-journal",1, 0, WriteJournal},
5308f117 154 {"consistency-policy", 1, 0, 'k'},
64c4757e
NB
155
156 /* For assemble */
157 {"uuid", 1, 0, 'u'},
1c7a808c 158 {"super-minor",1,0, SuperMinor},
947fd4dd 159 {"name", 1, 0, 'N'},
1c7a808c 160 {"config", 1, 0, ConfigFile},
64c4757e 161 {"scan", 0, 0, 's'},
1c7a808c 162 {"force", 0, 0, Force},
5787fa49 163 {"update", 1, 0, 'U'},
b76b30e0 164 {"freeze-reshape", 0, 0, FreezeReshape},
dfd4d8ee 165
64c4757e 166 /* Management */
1c7a808c 167 {"add", 0, 0, Add},
f33a71f1 168 {"add-spare", 0, 0, AddSpare},
01290056 169 {"add-journal", 0, 0, AddJournal},
1c7a808c
N
170 {"remove", 0, 0, Remove},
171 {"fail", 0, 0, Fail},
172 {"set-faulty",0, 0, Fail},
70c55e36
N
173 {"replace", 0, 0, Replace},
174 {"with", 0, 0, With},
64c4757e
NB
175 {"run", 0, 0, 'R'},
176 {"stop", 0, 0, 'S'},
177 {"readonly", 0, 0, 'o'},
178 {"readwrite", 0, 0, 'w'},
997aed5d 179 {"no-degraded",0,0, NoDegraded },
1c7a808c 180 {"wait", 0, 0, WaitOpt},
1770662b 181 {"wait-clean", 0, 0, Waitclean },
a740cf64 182 {"action", 1, 0, Action },
4de90913 183 {"cluster-confirm", 0, 0, ClusterConfirm},
52826846 184
cd29a5c8 185 /* For Detail/Examine */
1c7a808c 186 {"brief", 0, 0, Brief},
d11abe4b 187 {"no-devices",0, 0, NoDevices},
54bad364 188 {"export", 0, 0, 'Y'},
997aed5d 189 {"sparc2.2", 0, 0, Sparc22},
feb716e9 190 {"test", 0, 0, 't'},
c2ecf5f6 191 {"prefer", 1, 0, Prefer},
cd29a5c8 192
52826846 193 /* For Follow/monitor */
1c7a808c
N
194 {"mail", 1, 0, EMail},
195 {"program", 1, 0, ProgramOpt},
196 {"alert", 1, 0, ProgramOpt},
197 {"increment", 1, 0, Increment},
52826846 198 {"delay", 1, 0, 'd'},
1c7a808c
N
199 {"daemonise", 0, 0, Fork},
200 {"daemonize", 0, 0, Fork},
aa88f531 201 {"oneshot", 0, 0, '1'},
b5e64645 202 {"pid-file", 1, 0, 'i'},
90cf1ddd 203 {"syslog", 0, 0, 'y'},
edde9560
AC
204 {"no-sharing", 0, 0, NoSharing},
205
06b0d786 206 /* For Grow */
997aed5d 207 {"backup-file", 1,0, BackupFile},
87f26d14 208 {"invalid-backup",0,0,InvalidBackup},
84e11361 209 {"array-size", 1, 0, 'Z'},
2dddadb0 210 {"continue", 0, 0, Continue},
8382f19b
NB
211
212 /* For Incremental */
1c7a808c 213 {"rebuild-map", 0, 0, RebuildMapOpt},
950bc344
PC
214 {"path", 1, 0, IncrementalPath},
215
64c4757e
NB
216 {0, 0, 0, 0}
217};
218
219char Usage[] =
9a9dab36 220"Usage: mdadm --help\n"
64c4757e
NB
221" for help\n"
222;
223
224char Help[] =
e5a5d81e
NB
225"mdadm is used for building, managing, and monitoring\n"
226"Linux md devices (aka RAID arrays)\n"
9a9dab36 227"Usage: mdadm --create device options...\n"
e5a5d81e 228" Create a new array from unused devices.\n"
9a9dab36 229" mdadm --assemble device options...\n"
e968ba60 230" Assemble a previously created array.\n"
9a9dab36 231" mdadm --build device options...\n"
e5a5d81e 232" Create or assemble an array without metadata.\n"
e0d19036 233" mdadm --manage device options...\n"
e968ba60 234" make changes to an existing array.\n"
e0d19036 235" mdadm --misc options... devices\n"
e968ba60 236" report on or modify various md related devices.\n"
8382f19b
NB
237" mdadm --grow options device\n"
238" resize/reshape an active array\n"
239" mdadm --incremental device\n"
29ba4804 240" add/remove a device to/from an array as appropriate\n"
e0d19036 241" mdadm --monitor options...\n"
e968ba60 242" Monitor one or more array for significant changes.\n"
9a9dab36 243" mdadm device options...\n"
e968ba60 244" Shorthand for --manage.\n"
e5a5d81e
NB
245"Any parameter that does not start with '-' is treated as a device name\n"
246"or, for --examine-bitmap, a file name.\n"
247"The first such name is often the name of an md device. Subsequent\n"
248"names are often names of component devices.\n"
249"\n"
56eedc1a 250" For detailed help on the above major modes use --help after the mode\n"
e0d19036 251" e.g.\n"
9a9dab36 252" mdadm --assemble --help\n"
56eedc1a
NB
253" For general help on options use\n"
254" mdadm --help-options\n"
255;
256
257char OptionHelp[] =
64c4757e 258"Any parameter that does not start with '-' is treated as a device name\n"
c82f047c 259"or, for --examine-bitmap, a file name.\n"
e0d19036 260"The first such name is often the name of an md device. Subsequent\n"
e5a5d81e 261"names are often names of component devices.\n"
52826846 262"\n"
e0d19036 263"Some common options are:\n"
56eedc1a 264" --help -h : General help message or, after above option,\n"
64c4757e 265" mode specific help message\n"
56eedc1a 266" --help-options : This help message\n"
9a9dab36 267" --version -V : Print version information for mdadm\n"
64c4757e 268" --verbose -v : Be more verbose about what is happening\n"
dab6685f 269" --quiet -q : Don't print un-necessary messages\n"
e0d19036 270" --brief -b : Be less verbose, more brief\n"
e50cf220
MN
271" --export -Y : With --detail, --detail-platform or --examine use\n"
272" key=value format for easy import into environment\n"
e0d19036
NB
273" --force -f : Override normal checks and be more forceful\n"
274"\n"
275" --assemble -A : Assemble an array\n"
e5a5d81e 276" --build -B : Build an array without metadata\n"
e0d19036
NB
277" --create -C : Create a new array\n"
278" --detail -D : Display details of an array\n"
5787fa49 279" --examine -E : Examine superblock on an array component\n"
c82f047c 280" --examine-bitmap -X: Display the detail of a bitmap file\n"
6d388a88 281" --examine-badblocks: Display list of known bad blocks on device\n"
e0d19036 282" --monitor -F : monitor (follow) some arrays\n"
8382f19b 283" --grow -G : resize/ reshape and array\n"
29ba4804 284" --incremental -I : add/remove a single device to/from an array as appropriate\n"
e0d19036
NB
285" --query -Q : Display general information about how a\n"
286" device relates to the md driver\n"
1f48664b 287" --auto-detect : Start arrays auto-detected by the kernel\n"
e0d19036
NB
288;
289/*
64c4757e
NB
290"\n"
291" For create or build:\n"
c82f047c 292" --bitmap= -b : File to store bitmap in - may pre-exist for --build\n"
64c4757e 293" --chunk= -c : chunk size of kibibytes\n"
5787fa49 294" --rounding= : rounding factor for linear array (==chunk size)\n"
58380584
N
295" --level= -l : raid level: 0,1,4,5,6,10,linear, or mp for create.\n"
296" : 0,1,10,mp,faulty or linear for build.\n"
98c6faba 297" --parity= -p : raid5/6 parity algorithm: {left,right}-{,a}symmetric\n"
58380584 298" --layout= : same as --parity, for RAID10: [fno]NN \n"
b83d95f3 299" --raid-devices= -n : number of active devices in array\n"
58380584 300" --spare-devices= -x: number of spare (eXtra) devices in initial array\n"
e5329c37 301" --size= -z : Size (in K) of each drive in RAID1/4/5/6/10 - optional\n"
52826846
NB
302" --force -f : Honour devices as listed on command line. Don't\n"
303" : insert a missing drive for RAID5.\n"
58380584 304" --assume-clean : Assume the array is already in-sync. This is dangerous for RAID5.\n"
c82f047c
NB
305" --bitmap-chunk= : chunksize of bitmap in bitmap file (Kilobytes)\n"
306" --delay= -d : seconds between bitmap updates\n"
dfd4d8ee 307" --write-behind= : number of simultaneous write-behind requests to allow (requires bitmap)\n"
947fd4dd 308" --name= -N : Textual name for array - max 32 characters\n"
64c4757e
NB
309"\n"
310" For assemble:\n"
c82f047c 311" --bitmap= -b : File to find bitmap information in\n"
64c4757e
NB
312" --uuid= -u : uuid of array to assemble. Devices which don't\n"
313" have this uuid are excluded\n"
52826846
NB
314" --super-minor= -m : minor number to look for in super-block when\n"
315" choosing devices to use.\n"
947fd4dd 316" --name= -N : Array name to look for in super-block.\n"
64c4757e
NB
317" --config= -c : config file\n"
318" --scan -s : scan config file for missing information\n"
319" --force -f : Assemble the array even if some superblocks appear out-of-date\n"
cbfbcb0b 320" --update= -U : Update superblock: try '-A --update=?' for list of options.\n"
b8a8ccf9 321" --no-degraded : Do not start any degraded arrays - default unless --scan.\n"
64c4757e 322"\n"
cd29a5c8
NB
323" For detail or examine:\n"
324" --brief -b : Just print device name and UUID\n"
325"\n"
52826846
NB
326" For follow/monitor:\n"
327" --mail= -m : Address to mail alerts of failure to\n"
328" --program= -p : Program to run when an event is detected\n"
329" --alert= : same as --program\n"
330" --delay= -d : seconds of delay between polling state. default=60\n"
331"\n"
64c4757e
NB
332" General management:\n"
333" --add -a : add, or hotadd subsequent devices\n"
58380584 334" --re-add : re-add a recently removed device\n"
64c4757e 335" --remove -r : remove subsequent devices\n"
58380584 336" --fail -f : mark subsequent devices as faulty\n"
64c4757e 337" --set-faulty : same as --fail\n"
70c55e36 338" --replace : mark a device for replacement\n"
64c4757e 339" --run -R : start a partially built array\n"
5787fa49 340" --stop -S : deactivate array, releasing all resources\n"
64c4757e
NB
341" --readonly -o : mark array as readonly\n"
342" --readwrite -w : mark array as readwrite\n"
9a9dab36 343" --zero-superblock : erase the MD superblock from a device.\n"
b90c0e9a 344" --wait -W : wait for recovery/resync/reshape to finish.\n"
64c4757e 345;
e0d19036 346*/
64c4757e
NB
347
348char Help_create[] =
5c1dec3e 349"Usage: mdadm --create device --chunk=X --level=Y --raid-devices=Z devices\n"
64c4757e 350"\n"
aa88f531
NB
351" This usage will initialise a new md array, associate some\n"
352" devices with it, and activate the array. In order to create an\n"
353" array with some devices missing, use the special word 'missing' in\n"
354" place of the relevant device name.\n"
64c4757e 355"\n"
aa88f531 356" Before devices are added, they are checked to see if they already contain\n"
e0d19036 357" raid superblocks or filesystems. They are also checked to see if\n"
64c4757e 358" the variance in device size exceeds 1%.\n"
aa88f531
NB
359" If any discrepancy is found, the user will be prompted for confirmation\n"
360" before the array is created. The presence of a '--run' can override this\n"
64c4757e
NB
361" caution.\n"
362"\n"
e0d19036
NB
363" If the --size option is given then only that many kilobytes of each\n"
364" device is used, no matter how big each device is.\n"
682c7051 365" If no --size is given, the apparent size of the smallest drive given\n"
e0d19036
NB
366" is used for raid level 1 and greater, and the full device is used for\n"
367" other levels.\n"
682c7051 368"\n"
e0d19036 369" Options that are valid with --create (-C) are:\n"
5308f117
AP
370" --bitmap= -b : Create a bitmap for the array with the given filename\n"
371" : or an internal bitmap if 'internal' is given\n"
372" --chunk= -c : chunk size in kibibytes\n"
373" --rounding= : rounding factor for linear array (==chunk size)\n"
374" --level= -l : raid level: 0,1,4,5,6,10,linear,multipath and synonyms\n"
375" --parity= -p : raid5/6 parity algorithm: {left,right}-{,a}symmetric\n"
376" --layout= : same as --parity, for RAID10: [fno]NN \n"
377" --raid-devices= -n : number of active devices in array\n"
378" --spare-devices= -x : number of spare (eXtra) devices in initial array\n"
379" --size= -z : Size (in K) of each drive in RAID1/4/5/6/10 - optional\n"
380" --data-offset= : Space to leave between start of device and start\n"
381" : of array data.\n"
382" --force -f : Honour devices as listed on command line. Don't\n"
383" : insert a missing drive for RAID5.\n"
384" --run -R : insist of running the array even if not all\n"
385" : devices are present or some look odd.\n"
386" --readonly -o : start the array readonly - not supported yet.\n"
387" --name= -N : Textual name for array - max 32 characters\n"
388" --bitmap-chunk= : bitmap chunksize in Kilobytes.\n"
389" --delay= -d : bitmap update delay in seconds.\n"
390" --write-journal= : Specify journal device for RAID-4/5/6 array\n"
391" --consistency-policy= : Specify the policy that determines how the array\n"
392" -k : maintains consistency in case of unexpected shutdown.\n"
64c4757e
NB
393"\n"
394;
395
396char Help_build[] =
b83d95f3 397"Usage: mdadm --build device -chunk=X --level=Y --raid-devices=Z devices\n"
64c4757e
NB
398"\n"
399" This usage is similar to --create. The difference is that it creates\n"
e0d19036 400" a legacy array without a superblock. With these arrays there is no\n"
64c4757e
NB
401" different between initially creating the array and subsequently\n"
402" assembling the array, except that hopefully there is useful data\n"
403" there in the second case.\n"
404"\n"
58380584 405" The level may only be 0, 1, 10, linear, multipath, or faulty.\n"
64c4757e 406" All devices must be listed and the array will be started once complete.\n"
e0d19036 407" Options that are valid with --build (-B) are:\n"
c82f047c 408" --bitmap= : file to store/find bitmap information in.\n"
e0d19036 409" --chunk= -c : chunk size of kibibytes\n"
5787fa49 410" --rounding= : rounding factor for linear array (==chunk size)\n"
58380584 411" --level= -l : 0, 1, 10, linear, multipath, faulty\n"
c82f047c
NB
412" --raid-devices= -n : number of active devices in array\n"
413" --bitmap-chunk= : bitmap chunksize in Kilobytes.\n"
414" --delay= -d : bitmap update delay in seconds.\n"
64c4757e
NB
415;
416
417char Help_assemble[] =
9a9dab36
NB
418"Usage: mdadm --assemble device options...\n"
419" mdadm --assemble --scan options...\n"
64c4757e
NB
420"\n"
421"This usage assembles one or more raid arrays from pre-existing\n"
422"components.\n"
e0d19036 423"For each array, mdadm needs to know the md device, the identity of\n"
52826846
NB
424"the array, and a number of sub devices. These can be found in a number\n"
425"of ways.\n"
426"\n"
58380584
N
427"The md device is given on the command line, is found listed in the\n"
428"config file, or can be deduced from the array identity.\n"
429"The array identity is determined either from the --uuid, --name, or\n"
430"--super-minor commandline arguments, from the config file,\n"
52826846 431"or from the first component device on the command line.\n"
64c4757e 432"\n"
52826846
NB
433"The different combinations of these are as follows:\n"
434" If the --scan option is not given, then only devices and identities\n"
435" listed on the command line are considered.\n"
e0d19036 436" The first device will be the array device, and the remainder will be\n"
52826846
NB
437" examined when looking for components.\n"
438" If an explicit identity is given with --uuid or --super-minor, then\n"
e0d19036 439" only devices with a superblock which matches that identity is considered,\n"
52826846 440" otherwise every device listed is considered.\n"
64c4757e 441"\n"
52826846
NB
442" If the --scan option is given, and no devices are listed, then\n"
443" every array listed in the config file is considered for assembly.\n"
e0d19036 444" The identity of candidate devices are determined from the config file.\n"
58380584
N
445" After these arrays are assembled, mdadm will look for other devices\n"
446" that could form further arrays and tries to assemble them. This can\n"
447" be disabled using the 'AUTO' option in the config file.\n"
64c4757e 448"\n"
52826846
NB
449" If the --scan option is given as well as one or more devices, then\n"
450" Those devices are md devices that are to be assembled. Their identity\n"
451" and components are determined from the config file.\n"
64c4757e 452"\n"
b8a8ccf9
NB
453" If mdadm can not find all of the components for an array, it will assemble\n"
454" it but not activate it unless --run or --scan is given. To preserve this\n"
455" behaviour even with --scan, add --no-degraded. Note that \"all of the\n"
456" components\" means as many as were present the last time the array was running\n"
457" as recorded in the superblock. If the array was already degraded, and\n"
458" the missing device is not a new problem, it will still be assembled. It\n"
459" is only newly missing devices that cause the array not to be started.\n"
460"\n"
e0d19036 461"Options that are valid with --assemble (-A) are:\n"
58380584 462" --bitmap= : bitmap file to use with the array\n"
e0d19036
NB
463" --uuid= -u : uuid of array to assemble. Devices which don't\n"
464" have this uuid are excluded\n"
465" --super-minor= -m : minor number to look for in super-block when\n"
466" choosing devices to use.\n"
947fd4dd 467" --name= -N : Array name to look for in super-block.\n"
e0d19036
NB
468" --config= -c : config file\n"
469" --scan -s : scan config file for missing information\n"
470" --run -R : Try to start the array even if not enough devices\n"
471" for a full array are present\n"
472" --force -f : Assemble the array even if some superblocks appear\n"
473" : out-of-date. This involves modifying the superblocks.\n"
cbfbcb0b 474" --update= -U : Update superblock: try '-A --update=?' for option list.\n"
b8a8ccf9 475" --no-degraded : Assemble but do not start degraded arrays.\n"
0ea8f5b1 476" --readonly -o : Mark the array as read-only. No resync will start.\n"
e0d19036
NB
477;
478
479char Help_manage[] =
480"Usage: mdadm arraydevice options component devices...\n"
481"\n"
482"This usage is for managing the component devices within an array.\n"
483"The --manage option is not needed and is assumed if the first argument\n"
484"is a device name or a management option.\n"
58380584 485"The first device listed will be taken to be an md array device, any\n"
e0d19036
NB
486"subsequent devices are (potential) components of that array.\n"
487"\n"
488"Options that are valid with management mode are:\n"
489" --add -a : hotadd subsequent devices to the array\n"
58380584
N
490" --re-add : subsequent devices are re-added if there were\n"
491" : recent members of the array\n"
e0d19036
NB
492" --remove -r : remove subsequent devices, which must not be active\n"
493" --fail -f : mark subsequent devices a faulty\n"
494" --set-faulty : same as --fail\n"
70c55e36
N
495" --replace : mark device(s) to be replaced by spares. Once\n"
496" : replacement completes, device will be marked faulty\n"
497" --with : Indicate which spare a previous '--replace' should\n"
498" : prefer to use\n"
e0d19036 499" --run -R : start a partially built array\n"
5787fa49 500" --stop -S : deactivate array, releasing all resources\n"
e0d19036
NB
501" --readonly -o : mark array as readonly\n"
502" --readwrite -w : mark array as readwrite\n"
503;
504
505char Help_misc[] =
506"Usage: mdadm misc_option devices...\n"
507"\n"
508"This usage is for performing some task on one or more devices, which\n"
509"may be arrays or components, depending on the task.\n"
510"The --misc option is not needed (though it is allowed) and is assumed\n"
511"if the first argument in a misc option.\n"
512"\n"
513"Options that are valid with the miscellaneous mode are:\n"
514" --query -Q : Display general information about how a\n"
515" device relates to the md driver\n"
516" --detail -D : Display details of an array\n"
4cce4069 517" --detail-platform : Display hardware/firmware details\n"
5787fa49 518" --examine -E : Examine superblock on an array component\n"
c82f047c 519" --examine-bitmap -X: Display contents of a bitmap file\n"
6d388a88 520" --examine-badblocks: Display list of known bad blocks on device\n"
e0d19036
NB
521" --zero-superblock : erase the MD superblock from a device.\n"
522" --run -R : start a partially built array\n"
5787fa49 523" --stop -S : deactivate array, releasing all resources\n"
e0d19036
NB
524" --readonly -o : mark array as readonly\n"
525" --readwrite -w : mark array as readwrite\n"
feb716e9 526" --test -t : exit status 0 if ok, 1 if degrade, 2 if dead, 4 if missing\n"
b90c0e9a 527" --wait -W : wait for resync/rebuild/recovery to finish\n"
a740cf64 528" --action= : initiate or abort ('idle' or 'frozen') a 'check' or 'repair'.\n"
e0d19036
NB
529;
530
531char Help_monitor[] =
532"Usage: mdadm --monitor options devices\n"
533"\n"
534"This usage causes mdadm to monitor a number of md arrays by periodically\n"
535"polling their status and acting on any changes.\n"
536"If any devices are listed then those devices are monitored, otherwise\n"
537"all devices listed in the config file are monitored.\n"
538"The address for mailing advisories to, and the program to handle\n"
539"each change can be specified in the config file or on the command line.\n"
58380584
N
540"There must be at least one destination for advisories, whether\n"
541"an email address, a program, or --syslog\n"
e0d19036 542"\n"
dd0781e5 543"Options that are valid with the monitor (-F --follow) mode are:\n"
e0d19036
NB
544" --mail= -m : Address to mail alerts of failure to\n"
545" --program= -p : Program to run when an event is detected\n"
546" --alert= : same as --program\n"
237d8790 547" --syslog -y : Report alerts via syslog\n"
9a36a9b7 548" --increment= -r : Report RebuildNN events in the given increment. default=20\n"
e0d19036
NB
549" --delay= -d : seconds of delay between polling state. default=60\n"
550" --config= -c : specify a different config file\n"
551" --scan -s : find mail-address/program in config file\n"
d013a55e 552" --daemonise -f : Fork and continue in child, parent exits\n"
b5e64645 553" --pid-file= -i : In daemon mode write pid to specified file instead of stdout\n"
aa88f531 554" --oneshot -1 : Check for degraded arrays, then exit\n"
98c6faba 555" --test -t : Generate a TestMessage event against each array at startup\n"
e0d19036
NB
556;
557
dd0781e5
NB
558char Help_grow[] =
559"Usage: mdadm --grow device options\n"
560"\n"
561"This usage causes mdadm to attempt to reconfigure a running array.\n"
562"This is only possibly if the kernel being used supports a particular\n"
58380584 563"reconfiguration.\n"
dd0781e5 564"\n"
891d2994 565"Options that are valid with the grow (-G --grow) mode are:\n"
860f11ed
AP
566" --level= -l : Tell mdadm what level to convert the array to.\n"
567" --layout= -p : For a FAULTY array, set/change the error mode.\n"
568" : for other arrays, update the layout\n"
569" --size= -z : Change the active size of devices in an array.\n"
570" : This is useful if all devices have been replaced\n"
571" : with larger devices. Value is in Kilobytes, or\n"
572" : the special word 'max' meaning 'as large as possible'.\n"
573" --assume-clean : When increasing the --size, this flag will avoid\n"
574" : a resync of the new space\n"
575" --chunk= -c : Change the chunksize of the array\n"
576" --raid-devices= -n : Change the number of active devices in an array.\n"
577" --add= -a : Add listed devices as part of reshape. This is\n"
578" : needed for resizing a RAID0 which cannot have\n"
579" : spares already present.\n"
580" --bitmap= -b : Add or remove a write-intent bitmap.\n"
581" --backup-file= file : A file on a different device to store data for a\n"
582" : short time while increasing raid-devices on a\n"
583" : RAID4/5/6 array. Also needed throughout a reshape\n"
584" : when changing parameters other than raid-devices\n"
585" --array-size= -Z : Change visible size of array. This does not change any\n"
586" : data on the device, and is not stable across restarts.\n"
587" --data-offset= : Location on device to move start of data to.\n"
588" --consistency-policy= : Change the consistency policy of an active array.\n"
589" -k : Currently works only for PPL with RAID5.\n"
dd0781e5 590;
e0d19036 591
8382f19b 592char Help_incr[] =
29ba4804 593"Usage: mdadm --incremental [-Rqrsf] device\n"
8382f19b
NB
594"\n"
595"This usage allows for incremental assembly of md arrays. Devices can be\n"
596"added one at a time as they are discovered. Once an array has all expected\n"
597"devices, it will be started.\n"
598"\n"
29ba4804
N
599"Optionally, the process can be reversed by using the fail option.\n"
600"When fail mode is invoked, mdadm will see if the device belongs to an array\n"
601"and then both fail (if needed) and remove the device from that array.\n"
602"\n"
603"Options that are valid with incremental assembly (-I --incremental) are:\n"
604" --run -R : Run arrays as soon as a minimal number of devices are\n"
7e6140e6
N
605" : present rather than waiting for all expected.\n"
606" --quiet -q : Don't print any information messages, just errors.\n"
607" --rebuild-map -r : Rebuild the 'map' file that mdadm uses for tracking\n"
608" : partial arrays.\n"
609" --scan -s : Use with -R to start any arrays that have the minimal\n"
610" : required number of devices, but are not yet started.\n"
58380584
N
611" --fail -f : First fail (if needed) and then remove device from\n"
612" : any array that it is a member of.\n"
8382f19b 613;
e0d19036
NB
614
615char Help_config[] =
616"The /etc/mdadm.conf config file:\n\n"
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
N
638" Other configuration lines include:\n"
639" mailaddr, mailfrom, program used for --monitor mode\n"
640" create, auto used when creating device names in /dev\n"
641" homehost, policy, part-policy used to guide policy in various\n"
642" situations\n"
64c4757e
NB
643"\n"
644;
682c7051 645
5187a385
N
646char *mode_help[mode_count] = {
647 [0] = Help,
648 [ASSEMBLE] = Help_assemble,
649 [BUILD] = Help_build,
650 [CREATE] = Help_create,
651 [MANAGE] = Help_manage,
652 [MISC] = Help_misc,
653 [MONITOR] = Help_monitor,
654 [GROW] = Help_grow,
655 [INCREMENTAL] = Help_incr,
656};