blog/What_should_start_from__etc_rcS_d__in_Debian____almost_nothing.html

   1 <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
   2           "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
   3 <html xmlns="http://www.w3.org/1999/xhtml" dir="ltr">
   4   <head>
   5     <meta http-equiv="Content-Type" content="text/html;charset=utf-8" />
   6     <title>Petter Reinholdtsen: What should start from /etc/rcS.d/ in Debian? - almost nothing</title>
   7     <link rel="stylesheet" type="text/css" media="screen" href="http://people.skolelinux.org/pere/blog/style.css" />
   8     <link rel="stylesheet" type="text/css" media="screen" href="http://people.skolelinux.org/pere/blog/vim.css" />
   9   </head>
  10   <body>
  11     <div class="title">
  12  <h1>
  13      <a href="http://people.skolelinux.org/pere/blog/">Petter Reinholdtsen</a>
  14
  15  </h1>
  16
  17 </div>
  18
  19
  20     <div class="entry">
  21       <div class="title">What should start from /etc/rcS.d/ in Debian? - almost nothing</div>
  22       <div class="date">30th July 2011</div>
  23       <div class="body"><p>In the Debian boot system, several packages include scripts that
  24 are started from /etc/rcS.d/.  In fact, there is a bite more of them
  25 than make sense, and this causes a few problems.  What kind of
  26 problems, you might ask.  There are at least two problems.  The first
  27 is that it is not possible to recover a machine after switching to
  28 runlevel 1.  One need to actually reboot to get the machine back to
  29 the expected state.  The other is that single user boot will sometimes
  30 run into problems because some of the subsystems are activated before
  31 the root login is presented, causing problems when trying to recover a
  32 machine from a problem in that subsystem.  A minor additional point is
  33 that moving more scripts out of rcS.d/ and into the other rc#.d/
  34 directories will increase the amount of scripts that can run in
  35 parallel during boot, and thus decrease the boot time.</p>
  36
  37 <p>So, which scripts should start from rcS.d/.  In short, only the
  38 scripts that _have_ to execute before the root login prompt is
  39 presented during a single user boot should go there.  Everything else
  40 should go into the numeric runlevels.  This means things like
  41 lm-sensors, fuse and x11-common should not run from rcS.d, but from
  42 the numeric runlevels.  Today in Debian, there are around 115 init.d
  43 scripts that are started from rcS.d/, and most of them should be moved
  44 out.  Do your package have one of them?  Please help us make single
  45 user and runlevel 1 better by moving it.</p>
  46
  47 <p>Scripts setting up the screen, keyboard, system partitions
  48 etc. should still be started from rcS.d/, but there is for example no
  49 need to have the network enabled before the single user login prompt
  50 is presented.</p>
  51
  52 <p>As always, things are not so easy to fix as they sound.  To keep
  53 Debian systems working while scripts migrate and during upgrades, the
  54 scripts need to be moved from rcS.d/ to rc2.d/ in reverse dependency
  55 order, ie the scripts that nothing in rcS.d/ depend on can be moved,
  56 and the next ones can only be moved when their dependencies have been
  57 moved first.  This migration must be done sequentially while we ensure
  58 that the package system upgrade packages in the right order to keep
  59 the system state correct.  This will require some coordination when it
  60 comes to network related packages, but most of the packages with
  61 scripts that should migrate do not have anything in rcS.d/ depending
  62 on them.  Some packages have already been updated, like the sudo
  63 package, while others are still left to do.  I wish I had time to work
  64 on this myself, but real live constrains make it unlikely that I will
  65 find time to push this forward.</p>
  66 </div>
  67
  68       <div class="tags">Tags: <a href="http://people.skolelinux.org/pere/blog/tags/bootsystem">bootsystem</a>, <a href="http://people.skolelinux.org/pere/blog/tags/debian">debian</a>, <a href="http://people.skolelinux.org/pere/blog/tags/english">english</a>.</div>
  69
  70
  71     </div>
  72
  73
  74
  75
  76     <div id="sidebar">
  77
  78
  79
  80 <h2>Archive</h2>
  81 <ul>
  82
  83 <li>2012
  84 <ul>
  85
  86 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/01/">January (7)</a></li>
  87
  88 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/02/">February (10)</a></li>
  89
  90 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/03/">March (17)</a></li>
  91
  92 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/04/">April (12)</a></li>
  93
  94 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/05/">May (12)</a></li>
  95
  96 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/06/">June (20)</a></li>
  97
  98 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/07/">July (17)</a></li>
  99
 100 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/08/">August (6)</a></li>
 101
 102 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/09/">September (9)</a></li>
 103
 104 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/10/">October (17)</a></li>
 105
 106 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/11/">November (10)</a></li>
 107
 108 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/12/">December (2)</a></li>
 109
 110 </ul></li>
 111
 112 <li>2011
 113 <ul>
 114
 115 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/01/">January (16)</a></li>
 116
 117 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/02/">February (6)</a></li>
 118
 119 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/03/">March (6)</a></li>
 120
 121 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/04/">April (7)</a></li>
 122
 123 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/05/">May (3)</a></li>
 124
 125 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/06/">June (2)</a></li>
 126
 127 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/07/">July (7)</a></li>
 128
 129 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/08/">August (6)</a></li>
 130
 131 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/09/">September (4)</a></li>
 132
 133 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/10/">October (2)</a></li>
 134
 135 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/11/">November (3)</a></li>
 136
 137 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/12/">December (1)</a></li>
 138
 139 </ul></li>
 140
 141 <li>2010
 142 <ul>
 143
 144 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/01/">January (2)</a></li>
 145
 146 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/02/">February (1)</a></li>
 147
 148 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/03/">March (3)</a></li>
 149
 150 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/04/">April (3)</a></li>
 151
 152 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/05/">May (9)</a></li>
 153
 154 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/06/">June (14)</a></li>
 155
 156 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/07/">July (12)</a></li>
 157
 158 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/08/">August (13)</a></li>
 159
 160 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/09/">September (7)</a></li>
 161
 162 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/10/">October (9)</a></li>
 163
 164 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/11/">November (13)</a></li>
 165
 166 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/12/">December (12)</a></li>
 167
 168 </ul></li>
 169
 170 <li>2009
 171 <ul>
 172
 173 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/01/">January (8)</a></li>
 174
 175 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/02/">February (8)</a></li>
 176
 177 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/03/">March (12)</a></li>
 178
 179 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/04/">April (10)</a></li>
 180
 181 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/05/">May (9)</a></li>
 182
 183 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/06/">June (3)</a></li>
 184
 185 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/07/">July (4)</a></li>
 186
 187 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/08/">August (3)</a></li>
 188
 189 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/09/">September (1)</a></li>
 190
 191 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/10/">October (2)</a></li>
 192
 193 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/11/">November (3)</a></li>
 194
 195 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/12/">December (3)</a></li>
 196
 197 </ul></li>
 198
 199 <li>2008
 200 <ul>
 201
 202 <li><a href="http://people.skolelinux.org/pere/blog/archive/2008/11/">November (5)</a></li>
 203
 204 <li><a href="http://people.skolelinux.org/pere/blog/archive/2008/12/">December (7)</a></li>
 205
 206 </ul></li>
 207
 208 </ul>
 209
 210
 211
 212 <h2>Tags</h2>
 213 <ul>
 214
 215  <li><a href="http://people.skolelinux.org/pere/blog/tags/3d-printer">3d-printer (13)</a></li>
 216
 217  <li><a href="http://people.skolelinux.org/pere/blog/tags/amiga">amiga (1)</a></li>
 218
 219  <li><a href="http://people.skolelinux.org/pere/blog/tags/aros">aros (1)</a></li>
 220
 221  <li><a href="http://people.skolelinux.org/pere/blog/tags/bankid">bankid (3)</a></li>
 222
 223  <li><a href="http://people.skolelinux.org/pere/blog/tags/bitcoin">bitcoin (3)</a></li>
 224
 225  <li><a href="http://people.skolelinux.org/pere/blog/tags/bootsystem">bootsystem (12)</a></li>
 226
 227  <li><a href="http://people.skolelinux.org/pere/blog/tags/bsa">bsa (2)</a></li>
 228
 229  <li><a href="http://people.skolelinux.org/pere/blog/tags/debian">debian (57)</a></li>
 230
 231  <li><a href="http://people.skolelinux.org/pere/blog/tags/debian edu">debian edu (116)</a></li>
 232
 233  <li><a href="http://people.skolelinux.org/pere/blog/tags/digistan">digistan (9)</a></li>
 234
 235  <li><a href="http://people.skolelinux.org/pere/blog/tags/docbook">docbook (7)</a></li>
 236
 237  <li><a href="http://people.skolelinux.org/pere/blog/tags/drivstoffpriser">drivstoffpriser (4)</a></li>
 238
 239  <li><a href="http://people.skolelinux.org/pere/blog/tags/english">english (161)</a></li>
 240
 241  <li><a href="http://people.skolelinux.org/pere/blog/tags/fiksgatami">fiksgatami (21)</a></li>
 242
 243  <li><a href="http://people.skolelinux.org/pere/blog/tags/fildeling">fildeling (12)</a></li>
 244
 245  <li><a href="http://people.skolelinux.org/pere/blog/tags/freeculture">freeculture (9)</a></li>
 246
 247  <li><a href="http://people.skolelinux.org/pere/blog/tags/frikanalen">frikanalen (9)</a></li>
 248
 249  <li><a href="http://people.skolelinux.org/pere/blog/tags/intervju">intervju (32)</a></li>
 250
 251  <li><a href="http://people.skolelinux.org/pere/blog/tags/kart">kart (17)</a></li>
 252
 253  <li><a href="http://people.skolelinux.org/pere/blog/tags/ldap">ldap (8)</a></li>
 254
 255  <li><a href="http://people.skolelinux.org/pere/blog/tags/lenker">lenker (5)</a></li>
 256
 257  <li><a href="http://people.skolelinux.org/pere/blog/tags/ltsp">ltsp (1)</a></li>
 258
 259  <li><a href="http://people.skolelinux.org/pere/blog/tags/multimedia">multimedia (25)</a></li>
 260
 261  <li><a href="http://people.skolelinux.org/pere/blog/tags/norsk">norsk (217)</a></li>
 262
 263  <li><a href="http://people.skolelinux.org/pere/blog/tags/nuug">nuug (147)</a></li>
 264
 265  <li><a href="http://people.skolelinux.org/pere/blog/tags/offentlig innsyn">offentlig innsyn (6)</a></li>
 266
 267  <li><a href="http://people.skolelinux.org/pere/blog/tags/open311">open311 (2)</a></li>
 268
 269  <li><a href="http://people.skolelinux.org/pere/blog/tags/opphavsrett">opphavsrett (39)</a></li>
 270
 271  <li><a href="http://people.skolelinux.org/pere/blog/tags/personvern">personvern (60)</a></li>
 272
 273  <li><a href="http://people.skolelinux.org/pere/blog/tags/raid">raid (1)</a></li>
 274
 275  <li><a href="http://people.skolelinux.org/pere/blog/tags/reprap">reprap (11)</a></li>
 276
 277  <li><a href="http://people.skolelinux.org/pere/blog/tags/rfid">rfid (2)</a></li>
 278
 279  <li><a href="http://people.skolelinux.org/pere/blog/tags/robot">robot (4)</a></li>
 280
 281  <li><a href="http://people.skolelinux.org/pere/blog/tags/rss">rss (1)</a></li>
 282
 283  <li><a href="http://people.skolelinux.org/pere/blog/tags/ruter">ruter (4)</a></li>
 284
 285  <li><a href="http://people.skolelinux.org/pere/blog/tags/scraperwiki">scraperwiki (2)</a></li>
 286
 287  <li><a href="http://people.skolelinux.org/pere/blog/tags/sikkerhet">sikkerhet (28)</a></li>
 288
 289  <li><a href="http://people.skolelinux.org/pere/blog/tags/sitesummary">sitesummary (4)</a></li>
 290
 291  <li><a href="http://people.skolelinux.org/pere/blog/tags/skepsis">skepsis (4)</a></li>
 292
 293  <li><a href="http://people.skolelinux.org/pere/blog/tags/standard">standard (39)</a></li>
 294
 295  <li><a href="http://people.skolelinux.org/pere/blog/tags/stavekontroll">stavekontroll (3)</a></li>
 296
 297  <li><a href="http://people.skolelinux.org/pere/blog/tags/stortinget">stortinget (5)</a></li>
 298
 299  <li><a href="http://people.skolelinux.org/pere/blog/tags/surveillance">surveillance (12)</a></li>
 300
 301  <li><a href="http://people.skolelinux.org/pere/blog/tags/sysadmin">sysadmin (1)</a></li>
 302
 303  <li><a href="http://people.skolelinux.org/pere/blog/tags/valg">valg (7)</a></li>
 304
 305  <li><a href="http://people.skolelinux.org/pere/blog/tags/video">video (35)</a></li>
 306
 307  <li><a href="http://people.skolelinux.org/pere/blog/tags/vitenskap">vitenskap (4)</a></li>
 308
 309  <li><a href="http://people.skolelinux.org/pere/blog/tags/web">web (26)</a></li>
 310
 311 </ul>
 312
 313
 314     </div>
 315     <p style="text-align: right">
 316  Created by <a href="http://steve.org.uk/Software/chronicle">Chronicle v4.4</a>
 317 </p>
 318
 319   </body>
 320 </html>