initrd(4) Device Drivers Manual initrd(4) initrd - RAM-, /dev/initrd -- , , 1 250. , /dev/initrd root:disk 0400 ( root). /dev/initrd , : mknod -m 400 /dev/initrd b 1 250 chown root:disk /dev/initrd /dev/initrd << RAM>> << RAM>> Linux CONFIG_BLK_DEV_RAM=y CONFIG_BLK_DEV_INITRD=y. /dev/initrd RAM . /dev/initrd -- , . , , (.. ) . /dev/initrd . /dev/initrd (, RAM-, ). . (.., ). initrd : (1) /dev/initrd . (2) , /dev/initrd /dev/ram0, , /dev/initrd. (3) /dev/ram0 . (4) (, /dev/ram0), . (5) /linuxrc, UID 0. /linuxrc . /linuxrc , . (6) /linuxrc /linuxrc , . /linuxrc - , , . . (7) /initrd, /dev/ram0 / /initrd. , /initrd , /dev/ram0 . / /initrd /dev/ram0 , , /dev/ram0, . /initrd - /dev/ram0 /linuxrc, . . (8) (, /sbin/init) . initrd : initrd=_ , /dev/initrd. LOADLIN . LILO LILO -- /etc/lilo.config. , , , gzip. noinitrd . , /dev/initrd . /dev/initrd, , . /dev/initrd , . , /dev/initrd . root=_ , . LOADLIN LILO LILO -- /etc/lilo.config. , , , . , (, rdev(8) ) . NFS NFS nfs_root_name nfs_root_addrs. Documentation/filesystems/nfs/nfsroot.txt ( Documentation/filesystems/nfsroot.txt Linux 2.6.33). LILO LOADLIN. /linuxrc. /proc. /proc, /linuxrc proc- /proc/sys/kernel/real-root-dev, /proc/sys/kernel/nfs-root-name /proc/sys/kernel/nfs-root-addrs. /linuxrc /proc/sys/kernel/real-root-dev. NFS /linuxrc NFS /proc/sys/kernel/nfs-root-name /proc/sys/kernel/nfs-root-addrs, 0xff ( -NFS-) /proc/sys/kernel/real-root-dev. , , /dev/hdb1: echo 0x365 >/proc/sys/kernel/real-root-dev c NFS, NFS /var/nfsroot NFS- IP- 193.8.232.7 IP- 193.8.232.2 'idefix': 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 : /proc/sys/kernel/real-root-dev . Linux Documentation/admin-guide/initrd.rst ( Documentation/initrd.txt Linux 4.10), pivot_root(2) pivot_root(8). initrd . : (1) - (, /dev/ram, /dev/initrd ext2) /dev/initrd , gzip. (2) /linuxrc : (1) , (.., , , ) (2) (, CD-ROM, , , ). , . (3) /linuxrc . (4) /linuxrc ( ). (5) /linuxrc /proc/sys/kernel/real-root-dev, /proc, , , . (6) . (7) , , . (8) , /dev/initrd , (, /dev/ram0 , , , /dev/ram0 ). (9) , . /dev/initrd -- , . , initrd -- Linux . ( -- ) . . /linuxrc , /linuxrc. -- . , , , /dev/initrd / , , . , Linux CD-ROM initrd CD-ROM. LOADLIN /dev/initrd CD-ROM . LILO /dev/initrd RAM-, CD-ROM. /dev/initrd /dev/ram0 /linuxrc /initrd o , , /dev/ram0 / /initrd, . , /proc/mounts . o , /initrd , /dev/ram0 , /dev/ram0 - - . /dev/ram0 , /dev/ram0 . o /dev/initrd , . Linux . . chown(1), mknod(1), ram(4), freeramdisk(8), rdev(8) Documentation/admin-guide/initrd.rst ( Documentation/initrd.txt Linux 4.10) Linux, LILO, LOADLIN, SYSLINUX. Azamat Hackimov , Dmitriy S. Seregin , Yuri Kozlov ; GNU 3 , . . , , . Linux man-pages 6.06 31 2023 . initrd(4)