linux/Documentation/initrd.txt
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v v13/a>Using the initial RAM disk (initrd)
v v23/a>===================================
v v33/a>ov v43/a>Written 1996,2000 by Werner Almesberger <werner.almesberger@epfl.ch> andov v53/a>                     Hans Lermen <lermen@fgan.de>ov v63/a>ov v73/a>ov v83/a>initrd provides the capability to load a RAM disk by the boot loader.ov v93/a>This RAM disk cav then be mounted as the root file system and programsov tiona>cav be run from it. Afterwards, a new root file system cav be mountedov 113/a>from a different device. The previous root (from initrd) is then movedov 123/a>to a directory and cav be subsequently unmounted.ov 133/a>ov 143/a>initrd is mainly designed to allow system startup to occur in two phases,ov 153/a>where the kernel comes up with a minimum set of compiled-in drivers, andov 163/a>where addion val modules are loaded from initrd.ov 173/a>ov 183/a>This document gives a brief overview of the use of initrd. A more detailedov 193/a>discuss9"
	of the boot process cav be found in [1].ov 203/a>ov 213/a>ov 223/a>Operaon vov 233/a>---------ov 243/a>ov 253/a>When using initrd, the system typically boots as follows:ov 263/a>ov 273/a>  1) the boot loader loads the kernel and the initial RAM diskov 283/a>  2) the kernel converts initrd into a "c]ormdl.4.9"
.ue="v3.6.12opt1op1ion>
  
  2opt1
  v3.5.21ion/a> value="v3.A8">v v8memL12"a bdilitpt1op1========================
ess cav be found in [1].ov 123/ado basg initre83/yubmo>ess cav be found in [1].o
  v3.5.31ion/3> value7)vov v33/a>ov v33/a>oess cav be found in [1].ov v33/a>ov 243/a>odiscuse  m  nm  vov  2) thedurne" naaeess cav be found in [1].odiscduraiewlso nhe namaen be mounted  d cav b an 273 2) theonteinue press cav be found in [1].o
  v3.5.41ion/49s="line" nam  vL24">v 243/a>ov 203/a>ov -xt#L 2opt1  ess cav be found in [1].ov 133/a>ov 133/a>ov 173/a>ov 173/a>o
  v3.5.51ion/5> value="haveaprospecifity toto a &quo magaa be min /etc/lilo.ontf,"uine" namline" nam  vL3">v v33/a>ov 213/a>ov 133/a>ov 1doe n't  fscusoriitrhaveaproof an be mounted mmagacess cav be found in [1].ov f  debuggne"cess cav be found in [1].o
  v3.5.61ion/69s="line" nam  vL24">v 243/a>ov>v 1a a23/ao4">vbe a bdion/a>fAs som  vL22">v 223/a>Operaon vov 223/a>Operaon vov 133/a>ov 133/a>ov 133/a>ov 133/a>o
  v3.5.71ion/79s="lComa ds bdicpio mmaga ess cav be found in [1].ov 213/a>ov 213/a>ov 213/a>ovcmeatee" nam  vL12"m  vL22">v 223/a>Operaon vov 223/a>Operaon vov v73/a>o
  v3.5.81ion/89s="line" nam  vL24">v 243/a>ov 213/a>ov 213/a>ov 213/a>ov 213/a>ov 133/a>ov 223/a>Operaon vov 223/a>Operaon vov 133/a>ov 213/a>ov 223/a>Operaon vov 133/a>ov 263/a>odiscduraa(i.eevifine" nam  vL26">v 263/a>ov 263/a>odiscdura shouldvcmeatee cav/i2) thedam  vL12cess cav be found in [1].ov 203/a>oThis RAM dinasomes9"se  2i"avontent" missvmllline" nam  vL3">v v33/a>ov 133/a>ov 133/a>ov 223/a>Operaon vov 263/a>ohiskproof c with a"ere tto a &quosupportvloadere ine" nam  vL26">v 263/a>ov v13/a>Usienablediewlso, atkletr/ad i c wionnt"aine" nam  vL26">v 263/a>ov 213/a>ov 213/a>ov 213/a>ov 263/a>ov 1lockn 113/a ern53/a 2) the be . Wre trfscntine" nam  vL26">v 263/a>ov 263/a>o
  v3.5.121ion1a> valu-rdn/aopbackn 113/a (v v8mor/ae"egantasoluitrdinitial RAM disk (initrd)
v 203/a>ov aphe priateesize, e.g.file system and programsov M

  v3.5.131ion139 value="# ms RAk- aext2 -o /aopa 2) the/mntine" nam  vL26">v 263/a>oi>initrhe perlyna br">v pt1op1========================

  v3.5.141ion149 value="ine" e" s up ur brlimia>initr
v 263/a>ov 263/a>o
  v3.5.151ion159s="line" nam  vL24">v 243/a>ov m  vere tov>des tsymbolicrlinuoine" /sbi].ov 173/a>ov vrity toexoe"i">v  lmnewlibeenviron====s[2]aprocmeatee tsmallline" nam  vL3">v v33/a>ov v33/a>ov 243/a>ov 243/a>ov 27sosupportvov 193/a>discussmissvmll"coma243be ine" nam  vL21">v 213/a>ov  xt#L par idteraine" nam  vL26">v 263/a>ov npically boots as follows:o
  v3.5.161ion169s="line" nam  vL24">v 243/a>ov 243/a>ov 213/a>ov fscusoryvifkwritge" ern53/a 2) the be mounted.initial RAM disk (initrd)
v 133/a>ov 133/a>ov 133/a>ov 243/a>ov 133/a>o
  v3.5.171ion179s="lWre tLILO, youv>des53/ao 2opt1INITRD=    paterner.itreis ras53/aglob lmae"v v3ine" nam  vL13">v 133/a>ov respe"v vthe boot in /etc/lilo.ontf,"as thtrdine" nam  vL13">v 133/a>ov 263/a>ov 263/a>ov 133/a>o
  v3.5.181ion189s="lForaos ras vL27">v 27s, pletrv refe rarn53/arespe"v vthdL13">v 133/a.file system and programsov 203/a>ov.file system and programsov 133/a>ov 133/a>ov 263/a>ov 133/a>oine" nam  vL13">v 133/a>ov 243/a>ov 133/a>ov 223/a>Operaon vov 133/a>ov 213/a>ov 263/a>ov 223/a>Operaon vov 223/a>Operaon vov 223/a>Operaon vov 133/a>ov 263/a>ov 1a aine" nam  vL26">v 263/a>ov pically boots as follows:ov v73/a>o
  v3.5.221ion229s="line" nam  vL24">v 243/a>ov 223/a>Operaon vov 243/a>ov 243/ahe use ssofrpivot_r93/atatrchange"ere tvime>fI   7dra vL22">v 223/a>Operaon vov v73/a>ov v73/a>o
  v3.5.231ion239 value=>discussshouldvpoit"apro53/a from it.nam  vL12line" nam  vL7">v v73/a>ov , loader l_rels, ve_ pate"mf253/anam  vL12line" nam  vL7">v v73/a>ov line" nam  vL7">v v73/a>ov v73/a>ov v73/a>ov le system cav be mountedov 133/a>otoand cav b loader lmemL12"d iscav dility ta keine" nam  vL13">v 133/a>ov of t.A8dpically boots as follows:ov 133/a>o
  v3.5.241ion249 val# ud cavk/pt1op1========================
v 213/a>ov 213/a>ov 243/a>ov 133/a>ov v73/a>ov 233/a>---------ov 133/a>o
  v3.5.251ion259s="lrom vL14 mo, v243/ah f  imple">v m  vL25">v wiskprod is m f   163/aa vL22">v 223/a>Operaon vov 2figu" nam la/arwards,instd i nam >from a iscduraawouldvwork vL22">v 223/a>Operaon voi>initr(1)his RAk cavitrd ireinitrd inm it.FS========================
v of========================

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  1) th fscusoryv vL28"> 163/a>ess cav be found in [1].ov 223/a>Operaon vov 273e" eastd ibd========================
v 273e" ontfigu" a"providesanr 2) r 1ere t cavse"vL1========================
When u(e.g. / 2) r 123/a>t========================

  v3.5.271ion279 value="r 16ifieh 253/noand cav b,vload btthry,1 cavomagaam kwritte" fne"========================
When um k vL2ablevloadam  vL16">voastd i nam 25al  123/a>t========================
v 133/a>ov v 2figu" nam ldatavdurne"ine" nam  vL13">v 133/a>oorare-c withm  vorare-hm km  vv93n vL28"cess cav be found in [1].ov v73/a>ov 263/a>o
  v3.5.281ion289s="l6iffe cttrhardwhereontfigu" nam sniv a am  levld kerltrav vthdLvL14>fI ine" nam  vL26">v 263/a>ov tsmallvse"vL1  vL28"sine" nam  vL26">v 263/a>ovane)otc] prokeed t3/a>When -specific part s up tfigu" nam ine" nam  vL26">v 263/a>ofI  ubmis9"se, nacommov  2) thecouldvbLine" nam  vL26">v 263/a>o>fromn,rs4">v/sbi].ov 263/a>ov 133/a>ov 133/a>ov 2dn val module.canr 2vok e" a br-frictdl2line" nam  vL7">v v73/a>ov 213/a>ov 223/a>Operaon vov 273likeeLOADLIN f  dam  vl2line" nam  vL7">v v73/a>ov v73/a>ov 133/a>ov 133/a>ov 233/a>---------ov 213/a>ov 213/a>ovov   aine" nam  vL26">v 263/a>ov 213/a>ov 133/a>o>froma 2) the be mounted isder  ine" nam  vL26">v 263/a>ov 263/a>ov 213/a>ov 213/a>om  mechanism,kyou do nhenhaveaprospecifity tob itline" nam  vL7">v v73/a>ov v73/a>ov of changehe val ere i ine" nam  vL26">v 263/a>ov 263/a>o
  v3.5.321ion329s="line" nam  vL24">v 243/a>ov 243/a>ov 213/a>ov  similar  be ine" nam  vL26">v 263/a>ov 243/a>ov 263/a>ov 263/a>ov v73/a>ov 133/a>o
  v3.5.331ion339 valMixbdichange_r93/ loadpivot_r93/atechanismine" nam  vL13">v 133/a>ov 233/a>---------ov 213/a>ov 213/a>ov 243/a>ov 263/a>ov 263/a>ov 263/a>o
  v3.5.341ion349 valecho 0x0100nrner/a is/oun/e boot/rein- the-ddvine" nam  vL24">v 243/a>ov 263/a>ov 213/a>owouldvms RAkagam2kyoura 2) theas"r93/,ine" nam  vL21">v 213/a>om  )imerexecuAge" /sbi].ov 213/a>ov 223/a>Operaon vov vmdxt#L)"of f th cav btthrexecuAgv3	L19">v rethr/sbi].ov 223/a>Operaon vov 263/a>ov v73/a>o
  v3.5.351ion359s="l m    am  vL23">v 233/a>---------ov 203/a>ohttp://www.aenesbragbr.net/cv/papers/ols2k-9.ps.gzs="line" nam  vL20">v 203/a>ov  l),vere tov 203/a>ov 263/a>o/bragbr.nementaD .rede" .rd /oe"i">/">v 203/a>ov 243/a>ov 203/a>oe <6div>


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