UserUtilities.xml

   1 <?xml version="1.0" encoding="utf-8"?>
   2 <chapter xmlns="http://docbook.org/ns/docbook"
   3 xmlns:xl="http://www.w3.org/1999/xlink" version="5.0" xml:lang="en-US"
   4 xml:id="userutilities"
   5 xmlns:xi="http://www.w3.org/2001/XInclude">
   6   <title xml:id="userutilities.title">User Utilities</title>
   7   <para>This chapter describes user utilities.</para>
   8   <section xml:id="dbdoclet.50438206_94597">
   9     <title>
  10       <indexterm>
  11         <primary>lfs</primary>
  12       </indexterm>
  13       <literal>lfs</literal>
  14     </title>
  15     <para>The
  16     <literal>lfs</literal> utility can be used for user configuration routines
  17     and monitoring.</para>
  18     <section remap="h5">
  19       <title>Synopsis</title>
  20       <screen>
  21 lfs
  22 lfs changelog [--follow] <replaceable>mdt_name</replaceable> [startrec [endrec]]
  23 lfs changelog_clear <replaceable>mdt_name id endrec</replaceable>
  24 lfs check <replaceable>mds|osts|servers</replaceable>
  25 lfs df [-i] [-h] [--pool]-p <replaceable>fsname</replaceable>[.<replaceable>pool</replaceable>] [<replaceable>path</replaceable>] [--lazy]
  26 lfs find [[!] --atime|-A [-+]N] [[!] --mtime|-M [-+]N]
  27          [[!] --ctime|-C [-+]N] [--maxdepth|-D N] [--name|-n <replaceable>pattern</replaceable>]
  28          [--print|-p] [--print0|-P] [[!] --obd|-O <replaceable>ost_name</replaceable>[,<replaceable>ost_name...</replaceable>]]
  29          [[!] --size|-S [+-]N[kMGTPE]] --type |-t {bcdflpsD}]
  30          [[!] --gid|-g|--group|-G <replaceable>gname|gid</replaceable>]
  31          [[!] --uid|-u|--user|-U <replaceable>uname|uid</replaceable>]
  32          <replaceable>dirname|filename</replaceable>
  33 lfs getname [-h]|[path...]
  34 lfs getstripe [--obd|-O <replaceable>ost_name</replaceable>] [--quiet|-q] [--verbose|-v]
  35               [--count|-c] [--index|-i | --offset|-o]
  36               [--size|-s] [--pool|-p] [--directory|-d]
  37               [--recursive|-r] [--raw|-R] [-M]
  38               <replaceable>dirname|filename</replaceable> ...
  39 lfs setstripe [--size|-s stripe_size] [--count|-c <replaceable>stripe_count</replaceable>]
  40               [--stripe-index|-i <replaceable>start_ost_index</replaceable>]
  41               [--ost-list|-o <replaceable>ost_indicies</replaceable>]
  42               [--pool|-p <replaceable>pool</replaceable>]
  43               <replaceable>dirname|filename</replaceable>
  44 lfs setstripe -d <replaceable>dir</replaceable>
  45 lfs osts [path]
  46 lfs poollist <replaceable>filesystem</replaceable>[.<replaceable>pool</replaceable>]| <replaceable>pathname</replaceable>
  47 lfs quota [-q] [-v] [-h] [-o <replaceable>obd_uuid</replaceable>|-I <replaceable>ost_idx</replaceable>|-i <replaceable>mdt_idx</replaceable>]
  48           [-u <replaceable>username|uid|-g</replaceable> <replaceable>group|gid</replaceable>] <replaceable>/mount_point</replaceable>
  49 lfs quota -t -u|-g <replaceable>/mount_point</replaceable>
  50 lfs quotacheck [-ug] <replaceable>/mount_point</replaceable>
  51 lfs quotachown [-i] <replaceable>/mount_point</replaceable>
  52 lfs quotainv [-ug] [-f] <replaceable>/mount_point</replaceable>
  53 lfs quotaon [-ugf] <replaceable>/mount_point</replaceable>
  54 lfs quotaoff [-ug] <replaceable>/mount_point</replaceable>
  55 lfs setquota {-u|--user|-g|--group} <replaceable>uname|uid|gname|gid</replaceable>
  56              [--block-softlimit <replaceable>block_softlimit</replaceable>]
  57              [--block-hardlimit <replaceable>block_hardlimit</replaceable>]
  58              [--inode-softlimit <replaceable>inode_softlimit</replaceable>]
  59              [--inode-hardlimit <replaceable>inode_hardlimit</replaceable>]
  60              <replaceable>/mount_point</replaceable>
  61 lfs setquota -u|--user|-g|--group <replaceable>uname|uid|gname|gid</replaceable>
  62              [-b <replaceable>block_softlimit</replaceable>] [-B <replaceable>block_hardlimit</replaceable>]
  63              [-i <replaceable>inode-softlimit</replaceable>] [-I <replaceable>inode_hardlimit</replaceable>]
  64              <replaceable>/mount_point</replaceable>
  65 lfs setquota -t -u|-g [--block-grace <replaceable>block_grace</replaceable>]
  66              [--inode-grace <replaceable>inode_grace</replaceable>]
  67              <replaceable>/mount_point</replaceable>
  68 lfs setquota -t -u|-g [-b <replaceable>block_grace</replaceable>] [-i <replaceable>inode_grace</replaceable>]
  69              <replaceable>/mount_point</replaceable>
  70 lfs help
  71 </screen>
  72       <note>
  73         <para>In the above example, the
  74         <literal>
  75           <replaceable>/mount_point</replaceable>
  76         </literal> parameter refers to the mount point of the Lustre file
  77         system.</para>
  78       </note>
  79       <note>
  80         <para>The old lfs quota output was very detailed and contained
  81         cluster-wide quota statistics (including cluster-wide limits for a
  82         user/group and cluster-wide usage for a user/group), as well as
  83         statistics for each MDS/OST. Now,
  84         <literal>lfs quota</literal> has been updated to provide only
  85         cluster-wide statistics, by default. To obtain the full report of
  86         cluster-wide limits, usage and statistics, use the
  87         <literal>-v</literal> option with
  88         <literal>lfs quota</literal>.</para>
  89       </note>
  90     </section>
  91     <section remap="h5">
  92       <title>Description</title>
  93       <para>The
  94       <literal>lfs</literal> utility is used to create a new file with a
  95       specific striping pattern, determine the default striping pattern, gather
  96       the extended attributes (object numbers and location) for a specific
  97       file, find files with specific attributes, list OST information or set
  98       quota limits. It can be invoked interactively without any arguments or in
  99       a non-interactive mode with one of the supported arguments.</para>
 100     </section>
 101     <section remap="h5">
 102       <title>Options</title>
 103       <para>The various
 104       <literal>lfs</literal> options are listed and described below. For a
 105       complete list of available options, type help at the
 106       <literal>lfs</literal> prompt.</para>
 107       <informaltable frame="all">
 108         <tgroup cols="3">
 109           <colspec colname="c1" colwidth="20*" />
 110           <colspec colname="c2" colwidth="30*" />
 111           <colspec colname="c3" colwidth="50*" />
 112           <thead>
 113             <row>
 114               <entry nameend="c2" namest="c1">
 115                 <para>
 116                   <emphasis role="bold">Option</emphasis>
 117                 </para>
 118               </entry>
 119               <entry>
 120                 <para>
 121                   <emphasis role="bold">Description</emphasis>
 122                 </para>
 123               </entry>
 124             </row>
 125           </thead>
 126           <tbody>
 127             <row>
 128               <entry nameend="c2" namest="c1">
 129                 <para>
 130                   <literal>changelog</literal>
 131                 </para>
 132               </entry>
 133               <entry>
 134                 <para>Shows the metadata changes on an MDT. Start and end
 135                 points are optional. The
 136                 <literal>--follow</literal> option blocks on new changes; this
 137                 option is only valid when run directly on the MDT node.</para>
 138               </entry>
 139             </row>
 140             <row>
 141               <entry nameend="c2" namest="c1">
 142                 <para>
 143                   <literal>changelog_clear</literal>
 144                 </para>
 145               </entry>
 146               <entry>
 147                 <para>Indicates that changelog records previous to
 148                 <literal>
 149                   <replaceable>endrec</replaceable>
 150                 </literal> are no longer of interest to a particular consumer
 151                 <literal>
 152                   <replaceable>id</replaceable>
 153                 </literal>, potentially allowing the MDT to free up disk space.
 154                 An
 155                 <literal>
 156                   <replaceable>endrec</replaceable>
 157                 </literal> of 0 indicates the current last record. Changelog
 158                 consumers must be registered on the MDT node using
 159                 <literal>lctl</literal>.</para>
 160               </entry>
 161             </row>
 162             <row>
 163               <entry nameend="c2" namest="c1">
 164                 <literal>check</literal>
 165               </entry>
 166               <entry>
 167                 <para>Displays the status of MDS or OSTs (as specified in the
 168                 command) or all servers (MDS and OSTs).</para>
 169               </entry>
 170             </row>
 171             <row>
 172               <entry nameend="c2" namest="c1">
 173                 <literal>df [-i] [-h] [--pool|-p
 174                 <replaceable>fsname</replaceable>[.
 175                 <replaceable>pool</replaceable>] [
 176                 <replaceable>path</replaceable>] [--lazy]</literal>
 177               </entry>
 178               <entry>
 179                 <para>Use
 180                 <literal>-i</literal> to report file system disk space usage or
 181                 inode usage of each MDT or OST or, if a pool is specified with
 182                 the
 183                 <literal>-p</literal> option, a subset of OSTs.</para>
 184                 <para>By default, the usage of all mounted Lustre file systems
 185                 is reported. If the
 186                 <literal>path</literal> option is included, only the usage for
 187                 the specified file system is reported. If the
 188                 <literal>-h</literal> option is included, the output is printed
 189                 in human-readable format, using SI base-2 suffixes for
 190                 <emphasis role="bold">M</emphasis>ega-,
 191                 <emphasis role="bold">G</emphasis>iga-,
 192                 <emphasis role="bold">T</emphasis>era-,
 193                 <emphasis role="bold">P</emphasis>eta-, or
 194                 <emphasis role="bold">E</emphasis>xabytes.</para>
 195                 <para>If the
 196                 <literal>--lazy</literal> option is specified, any OST that is
 197                 currently disconnected from the client will be skipped. Using
 198                 the
 199                 <literal>--lazy</literal> option prevents the
 200                 <literal>df</literal> output from being blocked when an OST is
 201                 offline. Only the space on the OSTs that can currently be
 202                 accessed are returned. The
 203                 <literal>llite.*.lazystatfs</literal> tunable can be enabled to
 204                 make this the default behaviour for all
 205                 <literal>statfs()</literal> operations.</para>
 206               </entry>
 207             </row>
 208             <row>
 209               <entry nameend="c2" namest="c1">
 210                 <para>
 211                   <literal>find</literal>
 212                 </para>
 213               </entry>
 214               <entry>
 215                 <para>Searches the directory tree rooted at the given
 216                 directory/filename for files that match the given
 217                 parameters.</para>
 218                 <para>Using
 219                 <literal>!</literal> before an option negates its meaning (files
 220                 NOT matching the parameter). Using
 221                 <literal>+</literal> before a numeric value means files with the
 222                 parameter OR MORE. Using
 223                 <literal>-</literal> before a numeric value means files with the
 224                 parameter OR LESS.</para>
 225               </entry>
 226             </row>
 227             <row>
 228               <entry />
 229               <entry>
 230                 <literal>--atime</literal>
 231               </entry>
 232               <entry>
 233                 <para>File was last accessed N*24 hours ago. (There is no
 234                 guarantee that
 235                 <literal>atime</literal> is kept coherent across the
 236                 cluster.)</para>
 237                 <para>OSTs store a transient
 238                 <literal>atime</literal> that is updated when clients do read
 239                 requests. Permanent
 240                 <literal>atime</literal> is written to the MDS when the file is
 241                 closed. However, on-disk atime is only updated if it is more
 242                 than 60 seconds old (
 243                 <literal>/proc/fs/lustre/mds/*/max_atime_diff</literal>). The
 244                 Lustre software considers the latest
 245                 <literal>atime</literal> from all OSTs. If a
 246                 <literal>setattr</literal> is set by user, then it is updated on
 247                 both the MDS and OST, allowing the
 248                 <literal>atime</literal> to go backward.</para>
 249               </entry>
 250             </row>
 251             <row>
 252               <entry>
 253                 <para>&#160;</para>
 254               </entry>
 255               <entry>
 256                 <para>
 257                   <literal>--ctime</literal>
 258                 </para>
 259               </entry>
 260               <entry>
 261                 <para>File status was last changed N*24 hours ago.</para>
 262               </entry>
 263             </row>
 264             <row>
 265               <entry>
 266                 <para>&#160;</para>
 267               </entry>
 268               <entry>
 269                 <para>
 270                   <literal>--mtime</literal>
 271                 </para>
 272               </entry>
 273               <entry>
 274                 <para>File data was last modified N*24 hours ago.</para>
 275               </entry>
 276             </row>
 277             <row>
 278               <entry>
 279                 <para>&#160;</para>
 280               </entry>
 281               <entry>
 282                 <para>
 283                   <literal>--obd</literal>
 284                 </para>
 285               </entry>
 286               <entry>
 287                 <para>File has an object on a specific OST(s).</para>
 288               </entry>
 289             </row>
 290             <row>
 291               <entry>
 292                 <para>&#160;</para>
 293               </entry>
 294               <entry>
 295                 <para>
 296                   <literal>--size</literal>
 297                 </para>
 298               </entry>
 299               <entry>
 300                 <para>File has a size in bytes, or kilo-, Mega-, Giga-, Tera-,
 301                 Peta- or Exabytes if a suffix is given.</para>
 302               </entry>
 303             </row>
 304             <row>
 305               <entry>
 306                 <para>&#160;</para>
 307               </entry>
 308               <entry>
 309                 <para>
 310                   <literal>--type</literal>
 311                 </para>
 312               </entry>
 313               <entry>
 314                 <para>File has the type - block, character, directory, pipe,
 315                 file, symlink, socket or door (used in Solaris operating
 316                 system).</para>
 317               </entry>
 318             </row>
 319             <row>
 320               <entry>
 321                 <para>&#160;</para>
 322               </entry>
 323               <entry>
 324                 <para>
 325                   <literal>--uid</literal>
 326                 </para>
 327               </entry>
 328               <entry>
 329                 <para>File has a specific numeric user ID.</para>
 330               </entry>
 331             </row>
 332             <row>
 333               <entry>
 334                 <para>&#160;</para>
 335               </entry>
 336               <entry>
 337                 <para>
 338                   <literal>--user</literal>
 339                 </para>
 340               </entry>
 341               <entry>
 342                 <para>File owned by a specific user (numeric user ID
 343                 allowed).</para>
 344               </entry>
 345             </row>
 346             <row>
 347               <entry>
 348                 <para>&#160;</para>
 349               </entry>
 350               <entry>
 351                 <para>
 352                   <literal>--gid</literal>
 353                 </para>
 354               </entry>
 355               <entry>
 356                 <para>File has a specific group ID.</para>
 357               </entry>
 358             </row>
 359             <row>
 360               <entry>
 361                 <para>&#160;</para>
 362               </entry>
 363               <entry>
 364                 <para>
 365                   <literal>--group</literal>
 366                 </para>
 367               </entry>
 368               <entry>
 369                 <para>File belongs to a specific group (numeric group ID
 370                 allowed).</para>
 371               </entry>
 372             </row>
 373             <row>
 374               <entry>
 375                 <para>&#160;</para>
 376               </entry>
 377               <entry>
 378                 <para>-
 379                 <literal>-maxdepth</literal></para>
 380               </entry>
 381               <entry>
 382                 <para>Limits find to descend at most N levels of the directory
 383                 tree.</para>
 384               </entry>
 385             </row>
 386             <row>
 387               <entry>
 388                 <para>&#160;</para>
 389               </entry>
 390               <entry>
 391                 <para>
 392                 <literal>--print</literal>/
 393                 <literal>--print0</literal></para>
 394               </entry>
 395               <entry>
 396                 <para>Prints the full filename, followed by a new line or NULL
 397                 character correspondingly.</para>
 398               </entry>
 399             </row>
 400             <row>
 401               <entry nameend="c2" namest="c1">
 402                 <para>
 403                   <literal>osts [path]</literal>
 404                 </para>
 405               </entry>
 406               <entry>
 407                 <para>Lists all OSTs for the file system. If a path located on
 408                 a mounted Lustre file system is specified, then only OSTs
 409                 belonging to this file system are displayed.</para>
 410               </entry>
 411             </row>
 412             <row>
 413               <entry nameend="c2" namest="c1">
 414                 <para>
 415                   <literal>getname [path...]</literal>
 416                 </para>
 417               </entry>
 418               <entry>
 419                 <para>List each Lustre file system instance associated with
 420                 each Lustre mount point. If no path is specified, all Lustre
 421                 mount points are interrogated. If a list of paths is provided,
 422                 the instance of each path is provided. If the path is not a
 423                 Lustre instance 'No such device' is returned.</para>
 424               </entry>
 425             </row>
 426             <row>
 427               <entry nameend="c2" namest="c1">
 428                 <para>
 429                   <literal>getstripe</literal>
 430                 </para>
 431               </entry>
 432               <entry>
 433                 <para>Lists striping information for a given filename or
 434                 directory. By default, the stripe count, stripe size and offset
 435                 are returned.</para>
 436                 <para>If you only want specific striping information, then the
 437                 options of
 438                 <literal>--count</literal>,
 439                 <literal>--size</literal>,
 440                 <literal>--index</literal> or
 441                 <literal>--offset</literal> plus various combinations of these
 442                 options can be used to retrieve specific information.</para>
 443                 <para>If the
 444                 <literal>--raw</literal> option is specified, the stripe
 445                 information is printed without substituting the file system
 446                 default values for unspecified fields. If the striping EA is
 447                 not set, 0, 0, and -1 will be printed for the stripe count,
 448                 size, and offset respectively.</para>
 449                 <para condition="l24">The
 450                 <literal>-M</literal> prints the index of the MDT for a given
 451                 directory. See
 452                 <xref linkend="dbdoclet.rmremotedir" />.</para>
 453               </entry>
 454             </row>
 455             <row>
 456               <entry>
 457                 <para>&#160;</para>
 458               </entry>
 459               <entry>
 460                 <para>
 461                   <literal>--obd
 462                   <replaceable>ost_name</replaceable></literal>
 463                 </para>
 464               </entry>
 465               <entry>
 466                 <para>Lists files that have an object on a specific OST.</para>
 467               </entry>
 468             </row>
 469             <row>
 470               <entry>
 471                 <para>&#160;</para>
 472               </entry>
 473               <entry>
 474                 <para>
 475                   <literal>--quiet</literal>
 476                 </para>
 477               </entry>
 478               <entry>
 479                 <para>Lists details about the file's object ID
 480                 information.</para>
 481               </entry>
 482             </row>
 483             <row>
 484               <entry>
 485                 <para>&#160;</para>
 486               </entry>
 487               <entry>
 488                 <para>
 489                   <literal>--verbose</literal>
 490                 </para>
 491               </entry>
 492               <entry>
 493                 <para>Prints additional striping information.</para>
 494               </entry>
 495             </row>
 496             <row>
 497               <entry>
 498                 <para>&#160;</para>
 499               </entry>
 500               <entry>
 501                 <para>
 502                   <literal>--count</literal>
 503                 </para>
 504               </entry>
 505               <entry>
 506                 <para>Lists the stripe count (how many OSTs to use).</para>
 507               </entry>
 508             </row>
 509             <row>
 510               <entry>
 511                 <para>&#160;</para>
 512               </entry>
 513               <entry>
 514                 <para>
 515                   <literal>--index</literal>
 516                 </para>
 517               </entry>
 518               <entry>
 519                 <para>Lists the index for each OST in the file system.</para>
 520               </entry>
 521             </row>
 522             <row>
 523               <entry>
 524                 <para>&#160;</para>
 525               </entry>
 526               <entry>
 527                 <para>
 528                   <literal>--offset</literal>
 529                 </para>
 530               </entry>
 531               <entry>
 532                 <para>Lists the OST index on which file striping starts.</para>
 533               </entry>
 534             </row>
 535             <row>
 536               <entry>
 537                 <para>&#160;</para>
 538               </entry>
 539               <entry>
 540                 <para>
 541                   <literal>--pool</literal>
 542                 </para>
 543               </entry>
 544               <entry>
 545                 <para>Lists the pools to which a file belongs.</para>
 546               </entry>
 547             </row>
 548             <row>
 549               <entry>
 550                 <para>&#160;</para>
 551               </entry>
 552               <entry>
 553                 <para>
 554                   <literal>--size</literal>
 555                 </para>
 556               </entry>
 557               <entry>
 558                 <para>Lists the stripe size (how much data to write to one OST
 559                 before moving to the next OST).</para>
 560               </entry>
 561             </row>
 562             <row>
 563               <entry>
 564                 <para>&#160;</para>
 565               </entry>
 566               <entry>
 567                 <para>
 568                   <literal>--directory</literal>
 569                 </para>
 570               </entry>
 571               <entry>
 572                 <para>Lists entries about a specified directory instead of its
 573                 contents (in the same manner as
 574                 <literal>ls -d</literal>).</para>
 575               </entry>
 576             </row>
 577             <row>
 578               <entry>
 579                 <para>&#160;</para>
 580               </entry>
 581               <entry>
 582                 <para>
 583                   <literal>--recursive</literal>
 584                 </para>
 585               </entry>
 586               <entry>
 587                 <para>Recurses into all sub-directories.</para>
 588               </entry>
 589             </row>
 590             <row>
 591               <entry nameend="c2" namest="c1">
 592                 <para>
 593                   <literal>setstripe</literal>
 594                 </para>
 595               </entry>
 596               <entry>
 597                 <para>Create new files with a specific file layout (stripe
 598                 pattern) configuration.
 599                 <footnote>
 600                   <para>The file cannot exist prior to using
 601                   <literal>setstripe</literal>. A directory must exist prior to
 602                   using
 603                   <literal>setstripe</literal>.</para>
 604                 </footnote></para>
 605               </entry>
 606             </row>
 607             <row>
 608               <entry>
 609                 <para>&#160;</para>
 610               </entry>
 611               <entry>
 612                 <para>
 613                   <literal>--count stripe_cnt</literal>
 614                 </para>
 615               </entry>
 616               <entry>
 617                 <para>Number of OSTs over which to stripe a file. A
 618                 <literal>stripe_cnt</literal> of 0 uses the file system-wide
 619                 default stripe count (default is 1). A
 620                 <literal>stripe_cnt</literal> of -1 stripes over all available
 621                 OSTs.</para>
 622               </entry>
 623             </row>
 624             <row>
 625               <entry>
 626                 <para>&#160;</para>
 627               </entry>
 628               <entry>
 629                 <para>
 630                 <literal>--size stripe_size</literal>
 631                 <footnote>
 632                   <para>The default stripe-size is 0. The default start-ost is
 633                   -1. Do NOT confuse them! If you set start-ost to 0, all new
 634                   file creations occur on OST 0 (seldom a good idea).</para>
 635                 </footnote>&#160;</para>
 636               </entry>
 637               <entry>
 638                 <para>Number of bytes to store on an OST before moving to the
 639                 next OST. A stripe_size of 0 uses the file system's default
 640                 stripe size, (default is 1 MB). Can be specified with
 641                 <emphasis role="bold">k</emphasis>(KB),
 642                 <emphasis role="bold">m</emphasis>(MB), or
 643                 <emphasis role="bold">g</emphasis>(GB), respectively.</para>
 644               </entry>
 645             </row>
 646             <row>
 647               <entry>
 648                 <para>&#160;</para>
 649               </entry>
 650               <entry>
 651                 <para>
 652                   <literal>--stripe-index start_ost_index</literal>
 653                 </para>
 654               </entry>
 655               <entry>
 656                 <para>The OST index (base 10, starting at 0) on which to start
 657                 striping for this file. A start_ost_index value of -1 allows
 658                 the MDS to choose the starting index. This is the default
 659                 value, and it means that the MDS selects the starting OST as it
 660                 wants. We strongly recommend selecting this default, as it
 661                 allows space and load balancing to be done by the MDS as
 662                 needed. The
 663                 <literal>start_ost_index</literal> value has no relevance on
 664                 whether the MDS will use round-robin or QoS weighted allocation
 665                 for the remaining stripes in the file.</para>
 666               </entry>
 667             </row>
 668             <row>
 669               <entry>
 670                 <para>&#160;</para>
 671               </entry>
 672               <entry>
 673                 <para>
 674                   <literal>--ost-index ost_indices</literal>
 675                 </para>
 676               </entry>
 677               <entry>
 678                                 <para>This option is used to specify the exact stripe
 679                 layout on the the file system. <literal>ost_indices</literal>
 680                 is a list of OSTs referenced by their indices and index ranges
 681                 separated by commas, e.g. <literal>1,2-4,7</literal>.</para>
 682               </entry>
 683             </row>
 684             <row>
 685               <entry>
 686                 <para>&#160;</para>
 687               </entry>
 688               <entry>
 689                 <para>
 690                   <literal>--pool
 691                   <replaceable>pool</replaceable></literal>
 692                 </para>
 693               </entry>
 694               <entry>
 695                 <para>Name of the pre-defined pool of OSTs (see
 696                 <xref linkend="dbdoclet.50438219_38274" />) that will be used
 697                 for striping. The
 698                 <literal>stripe_cnt</literal>,
 699                 <literal>stripe_size</literal> and
 700                 <literal>start_ost</literal> values are used as well. The
 701                 start-ost value must be part of the pool or an error is
 702                 returned.</para>
 703               </entry>
 704             </row>
 705             <row>
 706               <entry nameend="c2" namest="c1">
 707                 <para>
 708                   <literal>setstripe -d</literal>
 709                 </para>
 710               </entry>
 711               <entry>
 712                 <para>Deletes default striping on the specified
 713                 directory.</para>
 714               </entry>
 715             </row>
 716             <row>
 717               <entry nameend="c2" namest="c1">
 718                 <para>
 719                   <literal>poollist {filesystem}
 720                   [.poolname]|{pathname}</literal>
 721                 </para>
 722               </entry>
 723               <entry>
 724                 <para>Lists pools in the file system or pathname, or OSTs in
 725                 the file system's pool.</para>
 726               </entry>
 727             </row>
 728             <row>
 729               <entry nameend="c2" namest="c1">
 730                 <para>
 731                   <literal>quota [-q] [-v] [-o
 732                   <replaceable>obd_uuid</replaceable>|-i
 733                   <replaceable>mdt_idx</replaceable>|-I
 734                   <replaceable>ost_idx</replaceable>] [-u|-g
 735                   <replaceable>uname|uid|gname|gid]</replaceable>
 736                   <replaceable>/mount_point</replaceable></literal>
 737                 </para>
 738                 <para>&#160;</para>
 739               </entry>
 740               <entry>
 741                 <para>Displays disk usage and limits, either for the full file
 742                 system or for objects on a specific OBD. A user or group name
 743                 or an ID can be specified. If both user and group are omitted,
 744                 quotas for the current UID/GID are shown. The
 745                 <literal>-q</literal> option disables printing of additional
 746                 descriptions (including column titles). It fills in blank
 747                 spaces in the
 748                 <literal>grace</literal> column with zeros (when there is no
 749                 grace period set), to ensure that the number of columns is
 750                 consistent. The
 751                 <literal>-v</literal> option provides more verbose (per-OBD
 752                 statistics) output.</para>
 753               </entry>
 754             </row>
 755             <row>
 756               <entry nameend="c2" namest="c1">
 757                 <para>
 758                   <literal>quota -t
 759                   <replaceable>-u|-g</replaceable>
 760                   <replaceable>/mount_point</replaceable></literal>
 761                 </para>
 762               </entry>
 763               <entry>
 764                 <para>Displays block and inode grace times for user (
 765                 <literal>-u</literal>) or group (
 766                 <literal>-g</literal>) quotas.</para>
 767               </entry>
 768             </row>
 769             <row>
 770               <entry nameend="c2" namest="c1">
 771                 <para>
 772                   <literal>quotachown</literal>
 773                 </para>
 774               </entry>
 775               <entry>
 776                 <para>Changes the file's owner and group on OSTs of the
 777                 specified file system.</para>
 778               </entry>
 779             </row>
 780             <row>
 781               <entry nameend="c2" namest="c1">
 782                 <para>
 783                   <literal>quotacheck [-ugf]
 784                   <replaceable>/mount_point</replaceable></literal>
 785                 </para>
 786               </entry>
 787               <entry>
 788                 <para>Scans the specified file system for disk usage, and
 789                 creates or updates quota files. Options specify quota for users
 790                 (
 791                 <literal>-u</literal>), groups (
 792                 <literal>-g</literal>), and force (
 793                 <literal>-f</literal>).</para>
 794               </entry>
 795             </row>
 796             <row>
 797               <entry nameend="c2" namest="c1">
 798                 <para>
 799                   <literal>quotaon [-ugf]
 800                   <replaceable>/mount_point</replaceable></literal>
 801                 </para>
 802               </entry>
 803               <entry>
 804                 <para>Turns on file system quotas. Options specify quota for
 805                 users (
 806                 <literal>-u</literal>), groups (
 807                 <literal>-g</literal>), and force (
 808                 <literal>-f</literal>).</para>
 809               </entry>
 810             </row>
 811             <row>
 812               <entry nameend="c2" namest="c1">
 813                 <para>
 814                   <literal>quotaoff [-ugf]
 815                   <replaceable>/mount_point</replaceable></literal>
 816                 </para>
 817               </entry>
 818               <entry>
 819                 <para>Turns off file system quotas. Options specify quota for
 820                 users (
 821                 <literal>-u</literal>), groups (
 822                 <literal>-g</literal>), and force (
 823                 <literal>-f</literal>).</para>
 824               </entry>
 825             </row>
 826             <row>
 827               <entry nameend="c2" namest="c1">
 828                 <para>
 829                   <literal>quotainv [-ug] [-f]
 830                   <replaceable>/mount_point</replaceable></literal>
 831                 </para>
 832               </entry>
 833               <entry>
 834                 <para>Clears quota files (administrative quota files if used
 835                 without
 836                 <literal>-f</literal>, operational quota files otherwise), all
 837                 of their quota entries for users (
 838                 <literal>-u</literal>) or groups (
 839                 <literal>-g</literal>). After running
 840                 <literal>quotainv</literal>, you must run
 841                 <literal>quotacheck</literal> before using quotas.</para>
 842                 <caution>
 843                   <para>Use extreme caution when using this command; its
 844                   results cannot be undone.</para>
 845                 </caution>
 846               </entry>
 847             </row>
 848             <row>
 849               <entry nameend="c2" namest="c1">
 850                 <para>
 851                   <literal>setquota -u|-g
 852                   <replaceable>
 853                   uname|uid|gname|gid}</replaceable>[--block-softlimit
 854                   <replaceable>block_softlimit</replaceable>]
 855                   [--block-hardlimit
 856                   <replaceable>block_hardlimit</replaceable>]
 857                   [--inode-softlimit
 858                   <replaceable>inode_softlimit</replaceable>]
 859                   [--inode-hardlimit
 860                   <replaceable>inode_hardlimit</replaceable>]
 861                   <replaceable>/mount_point</replaceable></literal>
 862                 </para>
 863               </entry>
 864               <entry>
 865                 <para>Sets file system quotas for users or groups. Limits can
 866                 be specified with
 867                 <literal>--{block|inode}-{softlimit|hardlimit}</literal> or
 868                 their short equivalents
 869                 <literal>-b</literal>,
 870                 <literal>-B</literal>,
 871                 <literal>-i</literal>,
 872                 <literal>-I</literal>. Users can set 1, 2, 3 or 4 limits.
 873                 <footnote>
 874                   <para>The old
 875                   <literal>setquota</literal> interface is supported, but it may
 876                   be removed in a future Lustre software release.</para>
 877                 </footnote>Also, limits can be specified with special suffixes,
 878                 -b, -k, -m, -g, -t, and -p to indicate units of 1, 2^10, 2^20,
 879                 2^30, 2^40 and 2^50, respectively. By default, the block limits
 880                 unit is 1 kilobyte (1,024), and block limits are always
 881                 kilobyte-grained (even if specified in bytes). See
 882                 <xref linkend="dbdoclet.50438206_11903" />.</para>
 883               </entry>
 884             </row>
 885             <row>
 886               <entry nameend="c2" namest="c1">
 887                 <para>
 888                   <literal>setquota -t -u|-g [--block-grace
 889                   <replaceable>block_grace</replaceable>] [--inode-grace
 890                   <replaceable>inode_grace</replaceable>]
 891                   <replaceable>/mount_point</replaceable></literal>
 892                 </para>
 893               </entry>
 894               <entry>
 895                 <para>Sets the file system quota grace times for users or
 896                 groups. Grace time is specified in '
 897                 <literal>XXwXXdXXhXXmXXs</literal>' format or as an integer
 898                 seconds value. See
 899                 <xref linkend="dbdoclet.50438206_11903" />.</para>
 900               </entry>
 901             </row>
 902             <row>
 903               <entry nameend="c2" namest="c1">
 904                 <para>
 905                   <literal>help</literal>
 906                 </para>
 907               </entry>
 908               <entry>
 909                 <para>Provides brief help on various
 910                 <literal>lfs</literal> arguments.</para>
 911               </entry>
 912             </row>
 913             <row>
 914               <entry nameend="c2" namest="c1">
 915                 <para>
 916                   <literal>exit/quit</literal>
 917                 </para>
 918               </entry>
 919               <entry>
 920                 <para>Quits the interactive
 921                 <literal>lfs</literal> session.</para>
 922               </entry>
 923             </row>
 924           </tbody>
 925         </tgroup>
 926       </informaltable>
 927     </section>
 928     <section remap="h5">
 929       <title xml:id="dbdoclet.50438206_11903">Examples</title>
 930       <para>Creates a file striped on two OSTs with 128 KB on each
 931       stripe.</para>
 932       <screen>
 933 $ lfs setstripe -s 128k -c 2 /mnt/lustre/file1
 934 </screen>
 935       <para>Deletes a default stripe pattern on a given directory. New files
 936       use the default striping pattern.</para>
 937       <screen>
 938 $ lfs setstripe -d /mnt/lustre/dir
 939 </screen>
 940       <para>Lists the detailed object allocation of a given file.</para>
 941       <screen>
 942 $ lfs getstripe -v /mnt/lustre/file1
 943 </screen>
 944       <para>List all the mounted Lustre file systems and corresponding Lustre
 945       instances.</para>
 946       <screen>
 947 $ lfs getname
 948 </screen>
 949       <para>Efficiently lists all files in a given directory and its
 950       subdirectories.</para>
 951       <screen>
 952 $ lfs find /mnt/lustre
 953 </screen>
 954       <para>Recursively lists all regular files in a given directory more than
 955       30 days old.</para>
 956       <screen>
 957 $ lfs find /mnt/lustre -mtime +30 -type f -print
 958 </screen>
 959       <para>Recursively lists all files in a given directory that have objects
 960       on OST2-UUID. The lfs check servers command checks the status of all
 961       servers (MDT and OSTs).</para>
 962       <screen>
 963 $ lfs find --obd OST2-UUID /mnt/lustre/
 964 </screen>
 965       <para>Lists all OSTs in the file system.</para>
 966       <screen>
 967 $ lfs osts
 968 </screen>
 969       <para>Lists space usage per OST and MDT in human-readable format.</para>
 970       <screen>
 971 $ lfs df -h
 972 </screen>
 973       <para>Lists inode usage per OST and MDT.</para>
 974       <screen>
 975 $ lfs df -i
 976 </screen>
 977       <para>List space or inode usage for a specific OST pool.</para>
 978       <screen>
 979 $ lfs df --pool
 980 <replaceable>filesystem</replaceable>[.
 981 <replaceable>pool</replaceable>] |
 982 <replaceable>pathname</replaceable>
 983 </screen>
 984       <para>List quotas of user 'bob'.</para>
 985       <screen>
 986 $ lfs quota -u bob /mnt/lustre
 987 </screen>
 988       <para>Show grace times for user quotas on
 989       <literal>/mnt/lustre</literal>.</para>
 990       <screen>
 991 $ lfs quota -t -u /mnt/lustre
 992 </screen>
 993       <para>Changes file owner and group.</para>
 994       <screen>
 995 $ lfs quotachown -i /mnt/lustre
 996 </screen>
 997       <para>Checks quotas for user and group. Turns on quotas after making the
 998       check.</para>
 999       <screen>
1000 $ lfs quotacheck -ug /mnt/lustre
1001 </screen>
1002       <para>Turns on quotas of user and group.</para>
1003       <screen>
1004 $ lfs quotaon -ug /mnt/lustre
1005 </screen>
1006       <para>Turns off quotas of user and group.</para>
1007       <screen>
1008 $ lfs quotaoff -ug /mnt/lustre
1009 </screen>
1010       <para>Sets quotas of user 'bob', with a 1 GB block quota hardlimit and a
1011       2 GB block quota softlimit.</para>
1012       <screen>
1013 $ lfs setquota -u bob --block-softlimit 2000000 --block-hardlimit 1000000
1014 /mnt/lustre
1015 </screen>
1016       <para>Sets grace times for user quotas: 1000 seconds for block quotas, 1
1017       week and 4 days for inode quotas.</para>
1018       <screen>
1019 $ lfs setquota -t -u --block-grace 1000 --inode-grace 1w4d /mnt/lustre
1020 </screen>
1021       <para>Checks the status of all servers (MDT, OST)</para>
1022       <screen>
1023 $ lfs check servers
1024 </screen>
1025       <para>Creates a file striped on two OSTs from the pool
1026       <literal>my_pool</literal></para>
1027       <screen>
1028 $ lfs setstripe --pool my_pool -c 2 /mnt/lustre/file
1029 </screen>
1030       <para>Lists the pools defined for the mounted Lustre file system
1031       <literal>/mnt/lustre</literal></para>
1032       <screen>
1033 $ lfs poollist /mnt/lustre/
1034 </screen>
1035       <para>Lists the OSTs which are members of the pool
1036       <literal>my_pool</literal> in file system
1037       <literal>my_fs</literal></para>
1038       <screen>
1039 $ lfs poollist my_fs.my_pool
1040 </screen>
1041       <para>Finds all directories/files associated with
1042       <literal>poolA</literal>.</para>
1043       <screen>
1044 $ lfs find /mnt/lustre --pool poolA
1045 </screen>
1046       <para>Finds all directories/files not associated with a pool.</para>
1047       <screen>
1048 $ lfs find /mnt//lustre --pool ""
1049 </screen>
1050       <para>Finds all directories/files associated with pool.</para>
1051       <screen>
1052 $ lfs find /mnt/lustre ! --pool ""
1053 </screen>
1054       <para>Associates a directory with the pool
1055       <literal>my_pool</literal>, so all new files and directories are created
1056       in the pool.</para>
1057       <screen>
1058 $ lfs setstripe --pool my_pool /mnt/lustre/dir
1059 </screen>
1060     </section>
1061     <section remap="h5">
1062       <title>See Also</title>
1063       <para>
1064         <xref linkend="dbdoclet.50438219_38274" />
1065       </para>
1066     </section>
1067   </section>
1068   <section xml:id="dbdoclet.50438206_42260">
1069     <title>
1070       <indexterm>
1071         <primary>lfs_migrate</primary>
1072       </indexterm>
1073       <literal>lfs_migrate</literal>
1074     </title>
1075     <para>The
1076     <literal>lfs_migrate</literal> utility is a simple tool to migrate files
1077     between Lustre OSTs.</para>
1078     <section remap="h5">
1079       <title>Synopsis</title>
1080       <screen>
1081 lfs_migrate [-c <replaceable>stripecount</replaceable>] [-h] [-l] [-n] [-q] [-R] [-s] [-y]
1082 [file|directory ...]
1083 </screen>
1084     </section>
1085     <section remap="h5">
1086       <title>Description</title>
1087       <para>The
1088       <literal>lfs_migrate</literal> utility is a simple tool to assist
1089       migration of files between Lustre OSTs. The utility copies each specified
1090       file to a new file, verifies the file contents have not changed, and then
1091       renames the new file to the original filename. This allows balanced space
1092       usage between OSTs, moving files off OSTs that are starting to show
1093       hardware problems (though are still functional) or OSTs that will be
1094       discontinued.</para>
1095       <warning>
1096         <para>For versions of Lustre before 2.5,
1097         <literal>lfs_migrate</literal> is not closely integrated with the MDS,
1098         it cannot determine whether a file is currently open and/or in-use by
1099         other applications or nodes. This makes it UNSAFE for use on files that
1100         might be modified by other applications, since the migrated file is
1101         only a copy of the current file. This results in the old file becoming
1102         an open-unlinked file and any modifications to that file are
1103         lost.</para>
1104       </warning>
1105       <para>Files to be migrated can be specified as command-line arguments. If
1106       a directory is specified on the command-line then all files within the
1107       directory are migrated. If no files are specified on the command-line,
1108       then a list of files is read from the standard input, making
1109       <literal>lfs_migrate</literal> suitable for use with
1110       <literal>lfs</literal> find to locate files on specific OSTs and/or
1111       matching other file attributes.</para>
1112       <para>The current file allocation policies on the MDS dictate where the
1113       new files are placed, taking into account whether specific OSTs have been
1114       disabled on the MDS via
1115       <literal>lctl</literal>(preventing new files from being allocated there),
1116       whether some OSTs are overly full (reducing the number of files placed on
1117       those OSTs), or if there is a specific default file striping for the
1118       target directory (potentially changing the stripe count, stripe size, OST
1119       pool, or OST index of a new file).</para>
1120       <note>
1121         <para>The
1122         <literal>lfs_migrate</literal> utility can also be used in some cases to
1123         reduce file
1124         <indexterm>
1125           <primary>fragmentation</primary>
1126         </indexterm>fragmentation. File fragmentation will typically reduce
1127         Lustre file system performance. File fragmentation may be observed on
1128         an aged file system and will commonly occur if the file was written by
1129         many threads. Provided there is sufficient free space (or if it was
1130         written when the file system was nearly full) that is less fragmented
1131         than the file being copied, re-writing a file with
1132         <literal>lfs_migrate</literal> will result in a migrated file with
1133         reduced fragmentation. The tool
1134         <literal>filefrag</literal> can be used to report file fragmentation.
1135         See
1136         <xref linkend="dbdoclet.50438206_75125" /></para>
1137       </note>
1138       <note>
1139         <para>As long as a file has extent lengths of tens of megabytes (
1140         <replaceable>read_bandwidth * seek_time</replaceable>) or more, the
1141         read performance for the file will not be significantly impacted by
1142         fragmentation, since the read pipeline can be filled by large reads
1143         from disk even with an occasional disk seek.</para>
1144       </note>
1145     </section>
1146     <section remap="h5">
1147       <title>Options</title>
1148       <para>Options supporting
1149       <literal>lfs_migrate</literal> are described below.</para>
1150       <informaltable frame="all">
1151         <tgroup cols="2">
1152           <colspec colname="c1" colwidth="50*" />
1153           <colspec colname="c2" colwidth="50*" />
1154           <thead>
1155             <row>
1156               <entry>
1157                 <para>
1158                   <emphasis role="bold">Option</emphasis>
1159                 </para>
1160               </entry>
1161               <entry>
1162                 <para>
1163                   <emphasis role="bold">Description</emphasis>
1164                 </para>
1165               </entry>
1166             </row>
1167           </thead>
1168           <tbody>
1169             <row>
1170               <entry>
1171                 <para>
1172                   <literal>-c
1173                   <replaceable>stripecount</replaceable></literal>
1174                 </para>
1175               </entry>
1176               <entry>
1177                 <para>Restripe file using the specified stripe count. This
1178                 option may not be specified at the same time as the
1179                 <literal>-R</literal> option.</para>
1180               </entry>
1181             </row>
1182             <row>
1183               <entry>
1184                 <para>
1185                   <literal>-h</literal>
1186                 </para>
1187               </entry>
1188               <entry>
1189                 <para>Display help information.</para>
1190               </entry>
1191             </row>
1192             <row>
1193               <entry>
1194                 <literal>-l</literal>
1195               </entry>
1196               <entry>
1197                 <para>Migrate files with hard links (skips, by default). Files
1198                 with multiple hard links are split into multiple separate files
1199                 by
1200                 <literal>lfs_migrate</literal>, so they are skipped, by
1201                 default, to avoid breaking the hard links.</para>
1202               </entry>
1203             </row>
1204             <row>
1205               <entry>
1206                 <literal>-n</literal>
1207               </entry>
1208               <entry>
1209                 <para>Only print the names of files to be migrated.</para>
1210               </entry>
1211             </row>
1212             <row>
1213               <entry>
1214                 <para>
1215                   <literal>-q</literal>
1216                 </para>
1217               </entry>
1218               <entry>
1219                 <para>Run quietly (does not print filenames or status).</para>
1220               </entry>
1221             </row>
1222             <row>
1223               <entry>
1224                 <literal>-R</literal>
1225               </entry>
1226               <entry>Restripe file using default directory striping instead of
1227               keeping striping. This option may not be specified at the same
1228               time as the
1229               <literal>-c</literal> option.</entry>
1230             </row>
1231             <row>
1232               <entry>
1233                 <literal>-s</literal>
1234               </entry>
1235               <entry>Skip file data comparison after migrate. Default is to
1236               compare migrated file against original to verify
1237               correctness.</entry>
1238             </row>
1239             <row>
1240               <entry>
1241                 <para>
1242                   <literal>-y</literal>
1243                 </para>
1244               </entry>
1245               <entry>
1246                 <para>Answer '
1247                 <literal>y</literal>' to usage warning without prompting (for
1248                 scripts, use with caution).</para>
1249               </entry>
1250             </row>
1251           </tbody>
1252         </tgroup>
1253       </informaltable>
1254     </section>
1255     <section remap="h5">
1256       <title>Examples</title>
1257       <para>Rebalances all files in
1258       <literal>/mnt/lustre/dir</literal>.</para>
1259       <screen>
1260 $ lfs_migrate /mnt/lustre/file
1261 </screen>
1262       <para>Migrates files in /test filesystem on OST004 larger than 4 GB in
1263       size.</para>
1264       <screen>
1265 $ lfs find /test -obd test-OST004 -size +4G | lfs_migrate -y
1266 </screen>
1267     </section>
1268     <section remap="h5">
1269       <title>See Also</title>
1270       <para>
1271         <xref linkend="dbdoclet.50438206_94597" />
1272       </para>
1273     </section>
1274   </section>
1275   <section xml:id="dbdoclet.50438206_75125">
1276     <title>
1277       <indexterm>
1278         <primary>filefrag</primary>
1279       </indexterm>
1280       <literal>filefrag</literal>
1281     </title>
1282     <para>The
1283     <literal>e2fsprogs</literal> package contains the
1284     <literal>filefrag</literal> tool which reports the extent of file
1285     fragmentation.</para>
1286     <section remap="h5">
1287       <title>Synopsis</title>
1288       <screen>
1289 filefrag [ -belsv ] [ files...  ]
1290 </screen>
1291     </section>
1292     <section remap="h5">
1293       <title>Description</title>
1294       <para>The
1295       <literal>filefrag</literal> utility reports the extent of fragmentation in
1296       a given file. The
1297       <literal>filefrag</literal> utility obtains the extent information from
1298       Lustre files using the
1299       <literal>FIEMAP ioctl</literal>, which is efficient and fast, even for
1300       very large files.</para>
1301       <para>In default mode
1302       <footnote>
1303         <para>The default mode is faster than the verbose/extent mode since it
1304         only counts the number of extents.</para>
1305       </footnote>,
1306       <literal>filefrag</literal> prints the number of physically discontiguous
1307       extents in the file. In extent or verbose mode, each extent is printed
1308       with details such as the blocks allocated on each OST. For a Lustre file
1309       system, the extents are printed in device offset order (i.e. all of the
1310       extents for one OST first, then the next OST, etc.), not file logical
1311       offset order. If the file logical offset order was used, the Lustre
1312       striping would make the output very verbose and difficult to see if there
1313       was file fragmentation or not.</para>
1314       <note>
1315         <para>Note that as long as a file has extent lengths of tens of
1316         megabytes or more (i.e.
1317         <replaceable>read_bandwidth * seek_time &gt;
1318         extent_length</replaceable>), the read performance for the file will
1319         not be significantly impacted by fragmentation, since file readahead
1320         can fully utilize the disk disk bandwidth even with occasional
1321         seeks.</para>
1322       </note>
1323       <para>In default mode
1324       <footnote>
1325         <para>The default mode is faster than the verbose/extent mode.</para>
1326       </footnote>,
1327       <literal>filefrag</literal> returns the number of physically discontiguous
1328       extents in the file. In extent or verbose mode, each extent is printed
1329       with details. For a Lustre file system, the extents are printed in device
1330       offset order, not logical offset order.</para>
1331     </section>
1332     <section remap="h5">
1333       <title>Options</title>
1334       <para>The options and descriptions for the
1335       <literal>filefrag</literal> utility are listed below.</para>
1336       <informaltable frame="all">
1337         <tgroup cols="2">
1338           <colspec colname="c1" colwidth="50*" />
1339           <colspec colname="c2" colwidth="50*" />
1340           <thead>
1341             <row>
1342               <entry>
1343                 <para>
1344                   <emphasis role="bold">Option</emphasis>
1345                 </para>
1346               </entry>
1347               <entry>
1348                 <para>
1349                   <emphasis role="bold">Description</emphasis>
1350                 </para>
1351               </entry>
1352             </row>
1353           </thead>
1354           <tbody>
1355             <row>
1356               <entry>
1357                 <para>
1358                   <literal>-b</literal>
1359                 </para>
1360               </entry>
1361               <entry>
1362                 <para>Uses the 1024-byte blocksize for the output. By default,
1363                 this blocksize is used by the Lustre file system, since OSTs
1364                 may use different block sizes.</para>
1365               </entry>
1366             </row>
1367             <row>
1368               <entry>
1369                 <para>
1370                   <literal>-e</literal>
1371                 </para>
1372               </entry>
1373               <entry>
1374                 <para>Uses the extent mode when printing the output. This is
1375                 the default for Lustre files in verbose mode.</para>
1376               </entry>
1377             </row>
1378             <row>
1379               <entry>
1380                 <para>
1381                   <literal>-l</literal>
1382                 </para>
1383               </entry>
1384               <entry>
1385                 <para>Displays extents in LUN offset order. This is the only
1386                 available mode for Lustre.</para>
1387               </entry>
1388             </row>
1389             <row>
1390               <entry>
1391                 <para>
1392                   <literal>-s</literal>
1393                 </para>
1394               </entry>
1395               <entry>
1396                 <para>Synchronizes any unwritten file data to disk before
1397                 requesting the mapping.</para>
1398               </entry>
1399             </row>
1400             <row>
1401               <entry>
1402                 <para>
1403                   <literal>-v</literal>
1404                 </para>
1405               </entry>
1406               <entry>
1407                 <para>Prints the file's layout in verbose mode when checking
1408                 file fragmentation, including the logical to physical mapping
1409                 for each extent in the file and the OST index.</para>
1410               </entry>
1411             </row>
1412           </tbody>
1413         </tgroup>
1414       </informaltable>
1415     </section>
1416     <section remap="h5">
1417       <title>Examples</title>
1418       <para>Lists default output.</para>
1419       <screen>
1420 $ filefrag /mnt/lustre/foo
1421 /mnt/lustre/foo: 13 extents found
1422 </screen>
1423       <para>Lists verbose output in extent format.</para>
1424       <screen>
1425 $ filefrag -v /mnt/lustre/foo
1426 Filesystem type is: bd00bd0
1427 File size of /mnt/lustre/foo is 1468297786 (1433888 blocks of 1024 bytes)
1428  ext:     device_logical:        physical_offset: length:  dev: flags:
1429    0:        0..  122879: 2804679680..2804802559: 122880: 0002: network
1430    1:   122880..  245759: 2804817920..2804940799: 122880: 0002: network
1431    2:   245760..  278527: 2804948992..2804981759:  32768: 0002: network
1432    3:   278528..  360447: 2804982784..2805064703:  81920: 0002: network
1433    4:   360448..  483327: 2805080064..2805202943: 122880: 0002: network
1434    5:   483328..  606207: 2805211136..2805334015: 122880: 0002: network
1435    6:   606208..  729087: 2805342208..2805465087: 122880: 0002: network
1436    7:   729088..  851967: 2805473280..2805596159: 122880: 0002: network
1437    8:   851968..  974847: 2805604352..2805727231: 122880: 0002: network
1438    9:   974848.. 1097727: 2805735424..2805858303: 122880: 0002: network
1439   10:  1097728.. 1220607: 2805866496..2805989375: 122880: 0002: network
1440   11:  1220608.. 1343487: 2805997568..2806120447: 122880: 0002: network
1441   12:  1343488.. 1433599: 2806128640..2806218751:  90112: 0002: network
1442 /mnt/lustre/foo: 13 extents found
1443 </screen>
1444     </section>
1445   </section>
1446   <section xml:id="dbdoclet.50438206_86244">
1447     <title>
1448       <indexterm>
1449         <primary>mount</primary>
1450       </indexterm>
1451       <literal>mount</literal>
1452     </title>
1453     <para>The standard
1454     <literal>mount(8)</literal> Linux command is used to mount a Lustre file
1455     system. When mounting a Lustre file system, mount(8) executes the
1456     <literal>/sbin/mount.lustre</literal> command to complete the mount. The
1457     mount command supports these options specific to a Lustre file
1458     system:</para>
1459     <informaltable frame="all">
1460       <tgroup cols="2">
1461         <colspec colname="c1" colwidth="50*" />
1462         <colspec colname="c2" colwidth="50*" />
1463         <thead>
1464           <row>
1465             <entry>
1466               <para>
1467                 <emphasis role="bold">Server options</emphasis>
1468               </para>
1469             </entry>
1470             <entry>
1471               <para>
1472                 <emphasis role="bold">Description</emphasis>
1473               </para>
1474             </entry>
1475           </row>
1476         </thead>
1477         <tbody>
1478           <row>
1479             <entry>
1480               <para>
1481                 <literal>abort_recov</literal>
1482               </para>
1483             </entry>
1484             <entry>
1485               <para>Aborts recovery when starting a target</para>
1486             </entry>
1487           </row>
1488           <row>
1489             <entry>
1490               <para>
1491                 <literal>nosvc</literal>
1492               </para>
1493             </entry>
1494             <entry>
1495               <para>Starts only MGS/MGC servers</para>
1496             </entry>
1497           </row>
1498           <row>
1499             <entry>
1500               <para>
1501                 <literal>nomgs</literal>
1502               </para>
1503             </entry>
1504             <entry>
1505               <para>Start a MDT with a co-located MGS without starting the
1506               MGS</para>
1507             </entry>
1508           </row>
1509           <row>
1510             <entry>
1511               <para>
1512                 <literal>exclude</literal>
1513               </para>
1514             </entry>
1515             <entry>
1516               <para>Starts with a dead OST</para>
1517             </entry>
1518           </row>
1519           <row>
1520             <entry>
1521               <para>
1522                 <literal>md_stripe_cache_size</literal>
1523               </para>
1524             </entry>
1525             <entry>
1526               <para>Sets the stripe cache size for server side disk with a
1527               striped raid configuration</para>
1528             </entry>
1529           </row>
1530         </tbody>
1531       </tgroup>
1532     </informaltable>
1533     <informaltable frame="all">
1534       <tgroup cols="2">
1535         <colspec colname="c1" colwidth="50*" />
1536         <colspec colname="c2" colwidth="50*" />
1537         <thead>
1538           <row>
1539             <entry>
1540               <para>
1541                 <emphasis role="bold">Client options</emphasis>
1542               </para>
1543             </entry>
1544             <entry>
1545               <para>
1546                 <emphasis role="bold">Description</emphasis>
1547               </para>
1548             </entry>
1549           </row>
1550         </thead>
1551         <tbody>
1552           <row>
1553             <entry>
1554               <para>
1555                 <literal>flock/noflock/localflock</literal>
1556               </para>
1557             </entry>
1558             <entry>
1559               <para>Enables/disables global flock or local flock support</para>
1560             </entry>
1561           </row>
1562           <row>
1563             <entry>
1564               <para>
1565                 <literal>user_xattr/nouser_xattr</literal>
1566               </para>
1567             </entry>
1568             <entry>
1569               <para>Enables/disables user-extended attributes</para>
1570             </entry>
1571           </row>
1572           <row>
1573             <entry>
1574               <para>
1575                 <literal>user_fid2path/nouser_fid2path</literal>
1576               </para>
1577             </entry>
1578             <entry>
1579               <para condition="l23">Enables/disables FID to path translation by
1580               regular users</para>
1581             </entry>
1582           </row>
1583           <row>
1584             <entry>
1585               <para>
1586                 <literal>retry=</literal>
1587               </para>
1588             </entry>
1589             <entry>
1590               <para>Number of times a client will retry to mount the file
1591               system</para>
1592             </entry>
1593           </row>
1594         </tbody>
1595       </tgroup>
1596     </informaltable>
1597   </section>
1598   <section xml:id="dbdoclet.50438206_56217">
1599     <title>Handling Timeouts</title>
1600     <para>Timeouts are the most common cause of hung applications. After a
1601     timeout involving an MDS or failover OST, applications attempting to access
1602     the disconnected resource wait until the connection gets
1603     established.</para>
1604     <para>When a client performs any remote operation, it gives the server a
1605     reasonable amount of time to respond. If a server does not reply either due
1606     to a down network, hung server, or any other reason, a timeout occurs which
1607     requires a recovery.</para>
1608     <para>If a timeout occurs, a message (similar to this one), appears on the
1609     console of the client, and in
1610     <literal>/var/log/messages</literal>:</para>
1611     <screen>
1612 LustreError: 26597:(client.c:810:ptlrpc_expire_one_request()) @@@ timeout
1613
1614 req@a2d45200 x5886/t0 o38-&gt;mds_svc_UUID@NID_mds_UUID:12 lens 168/64 ref 1 fl
1615
1616 RPC:/0/0 rc 0
1617 </screen>
1618   </section>
1619 </chapter>