Linux Certif

Toute la documentation sur la certification Linux LPI

initrd

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initrd - ¥Ö¡¼¥È¥í¡¼¥À¤Ë¤è¤Ã¤Æ½é´ü²½¤µ¤ì¤¿ RAM ¥Ç¥£¥¹¥¯

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1. ¥Ö¡¼¥È¥í¡¼¥À¤Ï¥«¡¼¥Í¥ë¥×¥í¥°¥é¥à¤È /dev/initrd ¤ÎÆâÍƤò¥á¥â¥ê¤Ë¥í¡¼¥É¤¹¤ë¡£
2. ¥«¡¼¥Í¥ëµ¯Æ°»þ¡¢¥«¡¼¥Í¥ë¤Ï /dev/initrd ¥Ç¥Ð¥¤¥¹¤ÎÆâÍƤòŸ³« (uncompress) ¤·¡¢ /dev/ram0 ¤Ë¥³¥Ô¡¼¤¹¤ë¡£¤µ¤é¤Ë¡¢ /dev/initrd ¤Î»È¤Ã¤Æ¤¤¤¿¥á¥â¥ê¤ò²òÊü¤¹¤ë¡£
3. ¥«¡¼¥Í¥ë¤Ï /dev/ram0 ¥Ç¥Ð¥¤¥¹¤ò½é´ü¤Î¥ë¡¼¥È¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¤È¤·¤ÆÆɤ߽ñ¤­²Äǽ¤Ê·Á¼°¤Ç¥Þ¥¦¥ó ¥È¤¹¤ë¡£
4. »Ø¼¨¤µ¤ì¤¿¥ë¡¼¥È¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¤¬½é´ü¥ë¡¼¥È¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à (Î㤨¤Ð /dev/ram0) ¤ÈƱ°ì¤Î¾ì¹ç¤Ï¡¢¥«¡¼¥Í¥ë¤ÏÉáÄ̤Υ֡¼¥È¥·¡¼¥±¥ó¥¹¤Î¤¿¤á¤ÎºÇ¸å¤Î¥¹¥Æ¥Ã¥×¤ò ¾Êά¤¹¤ë¡£
5. /linuxrc ¤È¤¤¤¦¼Â¹Ô²Äǽ¤Ê¥Õ¥¡¥¤¥ë¤¬½é´ü¥ë¡¼¥È¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¤Ë¸ºß¤¹¤ì¤Ð¡¢ /linuxrc ¤ò UID 0 (¤¹¤Ê¤ï¤Á¡¢root) ¤Î¸¢¸Â¤Ç¼Â¹Ô¤¹¤ë¡£ (/linuxrc ¥Õ¥¡¥¤¥ë¤Ï¼Â¹Ô²Äǽ¥Ñ¡¼¥ß¥Ã¥·¥ç¥ó¤¬Í¿¤¨¤é¤ì¤Æ¤¤¤Ê¤±¤ì¤Ð¤Ê¤é¤Ê¤¤¡£ /linuxrc ¤ÏÀµÅö¤Ê¼Â¹Ô¥Õ¥¡¥¤¥ë¤Ç¤¢¤ì¤Ð¤è¤¯¡¢¥·¥§¥ë¥¹¥¯¥ê¥×¥È¤Ç¤â¹½¤ï¤Ê¤¤¡£)
6. /linuxrc ¤¬¼Â¹Ô¤µ¤ì¤Ê¤¤¡¢¤Þ¤¿¤Ï¡¢ /linuxrc ¤Î¼Â¹Ô¤¬½ªÎ»¤·¤¿»þ¤Ï¡¢Ä̾ï»þ¥ë¡¼¥È¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¤¬¥Þ¥¦¥ó¥È¤µ¤ì¤ë¡£ (/linuxrc ¤ò½ªÎ»¤·¤¿»þ¡¢²¿¤é¤«¤Î¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¤¬½é´ü¥ë¡¼¥È¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¾å¤Ë ¥Þ¥¦¥ó¥È¤µ¤ì¤Æ¤¤¤ë¾ì¹ç¤Î¥«¡¼¥Í¥ë¤ÎÆ°ºî¤Ï ·è¤á¤é¤ì¤Æ¤¤¤Ê¤¤ (ÉÔÄê¤Ç¤¢¤ë)¡£ ¸½ºß¤Î¥«¡¼¥Í¥ë¤¬¤É¤Î¤è¤¦¤ËÆ°ºî¤¹¤ë¤«¤Ï¡¢ Ãí°Õ ¤Î¥»¥¯¥·¥ç¥ó¤ò»²¾È¤Î¤³¤È¡£)
7. Ä̾ï»þ¥ë¡¼¥È¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¤Ë ¥Ç¥£¥ì¥¯¥È¥ê /initrd ¤¬¤¢¤ì¤Ð¡¢ /dev/ram0 ¥Ç¥Ð¥¤¥¹¤Ï / ¤«¤é /initrd ¤Ë°ÜÆ°¤µ¤ì¤ë¡£ /initrd ¥Ç¥£¥ì¥¯¥È¥ê¤¬Â¸ºß¤·¤Ê¤¤¾ì¹ç¤Ï¡¢ /dev/ram0 ¤Ï¥¢¥ó¥Þ¥¦¥ó¥È¤µ¤ì¤ë¡£ (/ ¤¬ /initrd ¤Ë°ÜÆ°¤µ¤ì¤¿¾ì¹ç¤Ë¤Ï¡¢ /dev/ram0 ¤Ï¥¢¥ó¥Þ¥¦¥ó¥È¤µ¤ì¤º¡¢¤½¤Î·ë²Ì¡¢ /dev/ram0 ¤ÇÁö¤ê»Ï¤á¤¿¥×¥í¥»¥¹¤Ï¤½¤Î¤Þ¤Þ»Ä¤ë»ö¤¬¤Ç¤­¤ë¡£ ¤â¤·¡¢ /initrd ¥Ç¥£¥ì¥¯¥È¥ê¤¬Ä̾ï»þ¥ë¡¼¥È¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¤Ë¸ºß¤»¤º¡¢ /linuxrc ¤¬½ªÎ»¤·¤¿»þ¤Ë /dev/ram0 ¾å¤Ç¼Â¹Ô¤µ¤ì¤¿¡¢¤Ê¤ó¤é¤«¤Î¥×¥í¥»¥¹¤¬Áö¤ê³¤±¤Æ¤¤¤¿¾ì¹ç¤Î ¥«¡¼¥Í¥ë¤ÎÆ°ºî¤Ï ·è¤á¤é¤ì¤Æ¤¤¤Ê¤¤ (ÉÔÄê¤Ç¤¢¤ë)¡£ ¸½ºß¤Î¥«¡¼¥Í¥ë¤¬¡¢¤³¤Î»þ¤É¤Î¤è¤¦¤ÊÆ°ºî¤ò¤¹¤ë¤«¤Ë¤Ä¤¤¤Æ¤Ï¡¢ Ãí°Õ ¤ò»²¾È¤Î¤³¤È¡£)
8. ÉáÄ̤Υ֡¼¥È¥·¡¼¥±¥ó¥¹ (Î㤨¤Ð¡¢ /sbin/init ¤Îµ¯Æ°) ¤¬Ä̾ï»þ¥ë¡¼¥È¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¾å¤Ç¹Ô¤ï¤ì¤ë¡£

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initrd=filename

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noinitrd

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root=device-name

Ä̾ï»þ¥ë¡¼¥È¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¤È¤·¤Æ»È¤ï¤ì¤ë¥Ç¥Ð¥¤¥¹¤ò»ØÄꤹ¤ë¡£ LOADLIN ¤Ç¤Ï¡¢¤³¤ì¤Ï¥³¥Þ¥ó¥É¥é¥¤¥ó¥ª¥×¥·¥ç¥ó¤Ç¤¢¤ë¡£ LILO ¤Ç¤Ï¥³¥Þ¥ó¥É¥é¥¤¥ó¥ª¥×¥·¥ç¥ó¡¢¤Þ¤¿¤Ï¡¢ LILO ¤ÎÀßÄê¥Õ¥¡¥¤¥ë¤Ç¤¢¤ë /etc/lilo.config ¤Î¥ª¥×¥·¥ç¥ó¥é¥¤¥ó¤È¤·¤Æ»ÈÍѤ¹¤ë¡£ ¤³¤Î¥ª¥×¥·¥ç¥ó¤Ç»ØÄꤵ¤ì¤ë¥Ç¥Ð¥¤¥¹¤Ï¡¢Å¬Àڤʥ롼¥È¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¤È¤· ¤Æ¥Þ¥¦¥ó¥È²Äǽ¤Ê¥Ç¥Ð¥¤¥¹¤Ç¤Ê¤±¤ì¤Ð¤Ê¤é¤Ê¤¤¡£

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¥Ç¥Õ¥©¥ë¥È¤Ç¤Ï¡¢¥«¡¼¥Í¥ë¤ÎÀßÄê (Î㤨¤Ð¡¢ rdev(8) ¤òÍѤ¤¤Æ¥«¡¼¥Í¥ë¥Õ¥¡¥¤¥ëÆâ¤Ë¥»¥Ã¥È¤µ¤ì¤¿¤â¤Î¡¢¤Þ¤¿¤Ï¡¢¥³¥ó¥Ñ¥¤¥ë»þ¤Ë¥«¡¼ ¥Í¥ë¥Õ¥¡¥¤¥ëÆâ¤ËËä¤á¹þ¤Þ¤ì¤¿¤â¤Î)¡¢ ¤Þ¤¿¤Ï¡¢¥Ö¡¼¥È¥í¡¼¥À¤Î¥ª¥×¥·¥ç¥óÀßÄê¤Ë¤è¤Ã¤Æ»ØÄꤵ¤ì¤¿¤â¤Î¤¬Ä̾ï»þ¥ë¡¼ ¥È¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¤È¤·¤Æ»È¤ï¤ì¤ë¡£ NFS ¥Þ¥¦¥ó¥È¤µ¤ì¤¿Ä̾ï»þ¥ë¡¼¥È¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¤òÍøÍѤ¹¤ë¾ì¹ç¡¢ nfs_root_name ¤È nfs_root_addrs ¥Ö¡¼¥È¥ª¥×¥·¥ç¥ó¤ò»È¤Ã¤Æ NFS ¤ÎÀßÄê¤òÍ¿¤¨¤Ê¤±¤ì¤Ð¤Ê¤é¤Ê¤¤¡£ NFS ¥Þ¥¦¥ó¥È¤µ¤ì¤¿¥ë¡¼¥È (¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à) ¤Ë¤Ä¤¤¤Æ¤Î ¤è¤ê¾Ü¤·¤¤¾ðÊó¤Ï¡¢¥«¡¼¥Í¥ë¤Î¥É¥­¥å¥á¥ó¥È¥Õ¥¡¥¤¥ë nfsroot.txt ¤ò»²¾È¤Î¤³¤È¡£ ¥ë¡¼¥È¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¤ÎÀßÄê¤Ë¤Ä¤¤¤Æ¤Î¤è¤ê¾Ü¤·¤¤¾ðÊó¤Ï¡¢ LILO ¤È LOADLIN ¤Î¥É¥­¥å¥á¥ó¥È¤ò»²¾È¤Î¤³¤È¡£

¤Þ¤¿¡¢ /linuxrc ¤òÍѤ¤¤ë»ö¤Ë¤è¤Ã¤Æ¤âÄ̾ï»þ¥ë¡¼¥È¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¥Ç¥Ð¥¤¥¹¤òÊѹ¹¤¹¤ë¤³¤È ¤¬¤Ç¤­¤ë¡£ /linuxrc ¤òÍѤ¤¤Æ¡¢Ä̾ï»þ¥ë¡¼¥È¥Ç¥Ð¥¤¥¹¤òÊѹ¹¤¹¤ë¤¿¤á¤Ë¤Ï¡¢ /proc ¤¬¥Þ¥¦¥ó¥È¤µ¤ì¤Æ¤¤¤Ê¤±¤ì¤Ð¤Ê¤é¤Ê¤¤¡£ /proc ¤ò¥Þ¥¦¥ó¥È¤·¤¿¸å¤Ç¡¢ /linuxrc ¤Ï proc ¥Õ¥¡¥¤¥ë /proc/sys/kernel/real-root-dev, /proc/sys/kernel/nfs-root-name, /proc/sys/kernel/nfs-root-addrs ¤Ë½ñ¤­¹þ¤ß¤ò¹Ô¤¤¡¢Ä̾ï»þ¥ë¡¼¥È¥Ç¥Ð¥¤¥¹¤òÊѹ¹¤¹¤ë¡£ (NFS ¤Ç¤Ï¤Ê¤¤) ʪÍýŪ¤Ê¥ë¡¼¥È¥Ç¥Ð¥¤¥¹¤Î¾ì¹ç¡¢ /linuxrc ¤¬¿·¤·¤¤¥ë¡¼¥È¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¤Î¥Ç¥Ð¥¤¥¹ÈÖ¹æ¤ò /proc/sys/kernel/real-root-dev ¤Ë½ñ¤­¹þ¤à¤³¤È¤Ç¡¢¥ë¡¼¥È¥Ç¥Ð¥¤¥¹¤¬Êѹ¹¤µ¤ì¤ë¡£ NFS ¥ë¡¼¥È¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¤Î¾ì¹ç¡¢ /linuxrc ¤¬ NFS ¤ÎÀßÄê¤ò /proc/sys/kernel/nfs-root-name ¤È /proc/sys/kernel/nfs-root-addrs ¤Ë½ñ¤­¹þ¤ß¡¢¤½¤ì¤«¤é /proc/sys/kernel/real-root-dev ¤Ë (µ¿»÷ NFS ¥Ç¥Ð¥¤¥¹¥Ê¥ó¥Ð¡¼¤Ç¤¢¤ë) 0xff ¤ò½ñ¤­¹þ¤à¤³¤È¤Ç¡¢ ¥ë¡¼¥È¥Ç¥Ð¥¤¥¹¤¬Êѹ¹¤µ¤ì¤ë¡£ Î㤨¤Ð¡¢¼¡¤Î¥·¥§¥ë¥³¥Þ¥ó¥É¥é¥¤¥ó¤Ë¤è¤ê¡¢Ä̾ï»þ¥ë¡¼¥È¥Ç¥Ð¥¤¥¹¤ò /dev/hdb1 ¤ËÊѹ¹¤Ç¤­¤ë¤À¤í¤¦:

    echo 0x365 >/proc/sys/kernel/real-root-dev

¤Þ¤¿¡¢NFS ¤Î¾ì¹ç¡¢¼¡¤Î¤è¤¦¤Ê¥·¥§¥ë¥³¥Þ¥ó¥É¥é¥¤¥ó¤Ë¤è¤ê¡¢ ¥í¡¼¥«¥ë¥Í¥Ã¥È¥ï¡¼¥¯¤Î 193.8.232.2 ¤È¤¤¤¦ IP ¥¢¥É¥ì¥¹¤ò»ý¤Ä NFS ¥µ¡¼¥Ð¤Î NFS ¥Ç¥£¥ì¥¯¥È¥ê /var/nfsroot ¤ò 193.8.232.7 ¤È¤¤¤¦ IP ¥¢¥É¥ì¥¹¤ò»ý¤Ä idefix ¤È¤¤¤¦Ì¾Á°¤Î¥· ¥¹¥Æ¥à¤ÎÄ̾ï»þ¥ë¡¼¥È¥Ç¥Ð¥¤¥¹¤È¤·¤Æ¥Þ¥¦¥ó¥È¤¹¤ë¤è¤¦¤ËÊѹ¹¤Ç¤­¤ë¤À¤í¤¦:

    echo /var/nfsroot >/proc/sys/kernel/nfs-root-name

    echo 193.8.232.2:193.8.232.7::255.255.255.0:idefix \

        >/proc/sys/kernel/nfs-root-addrs

    echo 255 >/proc/sys/kernel/real-root-dev

Ãí°Õ: ¥ë¡¼¥È¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¤òÊѹ¹¤¹¤ë¤¿¤á¤Ë /proc/sys/kernel/real-root-dev ¤ò»È¤¦¤Î¤Ï°ÊÁ°¤ÎÊýË¡¤Ç¤¢¤ë¡£ ¥ë¡¼¥È¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¤òÊѹ¹¤¹¤ë¿·¤·¤¤ÊýË¡¤Ë¤Ä¤¤¤Æ¤Î¾ðÊó¤Ï¡¢ ¥«¡¼¥Í¥ë¥½¡¼¥¹¤Ë´Þ¤Þ¤ì¤ë Documentation/initrd.txt ¥Õ¥¡¥¤¥ë¤ä¡¢ pivot_root(2) ¤ä pivot_root(8) ¤ò»²¾È¤·¤Æ¤Û¤·¤¤¡£

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2. ¼Â¹Ô¥Õ¥¡¥¤¥ë /linuxrc ¤Ï¡¢(1) Ä̾ï»þ¥ë¡¼¥È¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¤Î¥Þ¥¦¥ó¥È¤Ë²¿¤¬É¬Íפ« (¤¹¤Ê¤ï¤Á¡¢¥Ç¥Ð¥¤¥¹¥¿¥¤¥×¡¢¥Ç¥Ð¥¤¥¹¥É¥é¥¤¥Ð¡¢¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à)¡¢ (2) ÇÛÉÛ¥á¥Ç¥£¥¢¤Ë²¿¤¬É¬Íפ« (Î㤨¤Ð¡¢CD-ROM, ¥Í¥Ã¥È¥ï¡¼¥¯¡¢¥Æ¡¼¥×¤Ê¤É) ¤ò·èÄꤹ¤ë¡£·èÄê¤Ï¡¢¥æ¡¼¥¶¤Ø¤ÎÌ䤤¹ç¤ï¤»¡¢¼«Æ°¸¡½Ð¡¢¤¢¤ë¤¤¤Ï¤½¤Îξ¼Ô¤Î ÊýË¡¤òÁȤ߹ç¤ï¤»¤Æ¹Ô¤ï¤ì¤ë¡£
3. ¼Â¹Ô¥Õ¥¡¥¤¥ë /linuxrc ¤Ï¡¢½é´ü¥ë¡¼¥È¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¤«¤éɬÍפʥ⥸¥å¡¼¥ë¤ò¥í¡¼¥É¤¹¤ë¡£
4. ¼Â¹Ô¥Õ¥¡¥¤¥ë /linuxrc ¤Ï¡¢¥ë¡¼¥È¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¤òºîÀ®¤·¡¢ÇÛÃÖ¤¹¤ë (¤³¤ÎÃʳ¬¤Ç¤Ï¡¢Ä̾ï»þ¥ë¡¼ ¥È¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¤Ï´°Á´¤Ê¥·¥¹¥Æ¥à¤Ç¤¢¤ëɬÍפϤʤ¤)¡£
5. ¼Â¹Ô¥Õ¥¡¥¤¥ë /linuxrc ¤Ï¡¢ /proc/sys/kernel/real-root-dev ¤òÀßÄꤷ¡¢ /proc¡¢ ¥Þ¥¦¥ó¥È¤µ¤ì¤Æ¤¤¤ëÄ̾ï»þ¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥àµÚ¤Ó¤½¤Î¾¤Î¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à ¤ò¥¢¥ó¥Þ¥¦¥ó¥È¤·¡¢ ¼Â¹Ô¤ò½ªÎ»¤¹¤ë¡£
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