diff options
Diffstat (limited to '')
-rw-r--r-- | sys-utils/pivot_root.8.adoc | 77 |
1 files changed, 77 insertions, 0 deletions
diff --git a/sys-utils/pivot_root.8.adoc b/sys-utils/pivot_root.8.adoc new file mode 100644 index 0000000..9eba290 --- /dev/null +++ b/sys-utils/pivot_root.8.adoc @@ -0,0 +1,77 @@ +//po4a: entry man manual += pivot_root(8) +:doctype: manpage +:man manual: System Administration +:man source: util-linux {release-version} +:page-layout: base +:command: pivot_root + +== NAME + +pivot_root - change the root filesystem + +== SYNOPSIS + +*pivot_root* _new_root_ _put_old_ + +== DESCRIPTION + +*pivot_root* moves the root file system of the current process to the directory _put_old_ and makes _new_root_ the new root file system. Since *pivot_root*(8) simply calls *pivot_root*(2), we refer to the man page of the latter for further details. + +Note that, depending on the implementation of *pivot_root*, root and current working directory of the caller may or may not change. The following is a sequence for invoking *pivot_root* that works in either case, assuming that *pivot_root* and *chroot* are in the current *PATH*: + +.... +cd new_root +pivot_root . put_old +exec chroot . command +.... + +Note that *chroot* must be available under the old root and under the new root, because *pivot_root* may or may not have implicitly changed the root directory of the shell. + +Note that *exec chroot* changes the running executable, which is necessary if the old root directory should be unmounted afterwards. Also note that standard input, output, and error may still point to a device on the old root file system, keeping it busy. They can easily be changed when invoking *chroot* (see below; note the absence of leading slashes to make it work whether *pivot_root* has changed the shell's root or not). + +== OPTIONS + +include::man-common/help-version.adoc[] + +== EXAMPLE + +Change the root file system to _/dev/hda1_ from an interactive shell: + +.... +mount /dev/hda1 /new-root +cd /new-root +pivot_root . old-root +exec chroot . sh <dev/console >dev/console 2>&1 +umount /old-root +.... + +Mount the new root file system over NFS from 10.0.0.1:/my_root and run *init*: + +.... +ifconfig lo 127.0.0.1 up # for portmap +# configure Ethernet or such +portmap # for lockd (implicitly started by mount) +mount -o ro 10.0.0.1:/my_root /mnt +killall portmap # portmap keeps old root busy +cd /mnt +pivot_root . old_root +exec chroot . sh -c 'umount /old_root; exec /sbin/init' \ + <dev/console >dev/console 2>&1 +.... + +== SEE ALSO + +*chroot*(1), +*pivot_root*(2), +*mount*(8), +*switch_root*(8), +*umount*(8) + +include::man-common/bugreports.adoc[] + +include::man-common/footer.adoc[] + +ifdef::translation[] +include::man-common/translation.adoc[] +endif::[] |