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Diffstat (limited to 'disk-utils/README.bootutils-0.1')
| -rw-r--r-- | disk-utils/README.bootutils-0.1 | 104 |
1 files changed, 0 insertions, 104 deletions
diff --git a/disk-utils/README.bootutils-0.1 b/disk-utils/README.bootutils-0.1 deleted file mode 100644 index d87437e89..000000000 --- a/disk-utils/README.bootutils-0.1 +++ /dev/null @@ -1,104 +0,0 @@ -bootutils-0.1 - -* ALPHA RELEASE: Use at your own risk! * - -* You MUST have 0.99pl10 or later kernel to make use of all of the - facilities of this package. If you can live without the unmount-root - feature, then 0.99pl9 will work. * - -This is the first release of a set of utilities designed to automate -the management and checking of filesystems at boot time and shutdown. -It supports automatic and safe 'fsck' of all filesystems (including -root) at boot time by booting with root readonly; if the fsck succeeds -then root is remounted read-write and booting can continue. - -Why bother? - -Well, many people like to have a safe and reliable check of all their -filesystems during boot. This is especially true for ext2fs, because -all ext2fs filesystems have a special 'clean' flag which gets set when -the filesystem is cleaned (by e2fsck) or is unmounted cleanly, and -which gets unset when the filesystem is active. e2fsck can sense this -flag, and will skip over filesystems which are clean. - -This means that e2fsck won't bother you with a laborious filesystem -check at each startup, as long as you always shut down cleanly; but it -will check your filesystems automatically if you ever have a crash, -because afterwards the filesystem 'clean' flags will not be set. You -*can* still mount an unclean filesystem, but ext2fs will give you a -warning and will not mark it clean when it gets unmounted. - -One of the problems with automatic fsck'ing is that it is unsafe to -check mounted, active filesystems. The solution is to initially mount -only the root filesystem, and to mount it in readonly mode. In this -situation, fsck can run safely on all filesystems, without the danger -that the kernel might start conflicting with the repairs being done to -the filesystem. - -If any repairs were done, it is unsafe to proceed any further because -the kernel might have cached old information about the filesystems -which has been updated by fsck. However, if the fsck succeeded, then -we can remount the root filesystem in read-write mode and proceed to -mount all of the other filesystems. - -Finally, in order to ensure that filesystems are correctly tidied up -on shutdown, we need to unmount the root at shutdown. This is usually -done automatically; the standard Linux shutdown programs do a 'umount -- -a' command to unmount all mounted filesystems. You MUST have a -0.99pl10 or later kernel for this to work. Many versions of umount -explicitly do not try to unmount the root, since pre-99pl10 kernels -forbade this. The umount included here will unmount even the root -filesystem. (A special kernel trick in pl10 allows this to work by -keeping the filesystem alive in readonly mode after it has been tidied -up.) - -The bootup operation of this package is invoked by the /etc/rc shell -script, an example of which is in mount/etc/rc. It contains the -following important lines: - - # Check the integrity of all filesystems - /bin/fsck -A -a - # If there was a failure, drop into single-user mode. - if [ $? -gt 1 ] ; then - echo fsck failed. Please reboot. - sh - fi - - # Remount the root filesystem in read-write mode - /etc/mount -n -o remount /dev/hda3 / - - # remove /etc/mtab* so that mount will create it with a root entry - /bin/rm -f /etc/mtab* /etc/nologin /etc/utmp - - # mount file systems in fstab (and create an entry for /) - # but not NFS because TCP/IP is not yet configured - /etc/mount -avt nonfs - - -This is the first attempt at a complete package for automated clean -fsck support, so you may well find that you would like a slightly -different behaviour. Please feel free to send me comments, bug -reports and improvements! - - -This package includes three separate items, shamelessly adapted from -other, more or less standard Linux programs. - -* rdev.c: a modified rdev which is extended to allow the - readonly/readwrite status of the kernel image to be altered. Use - rdev -R <kernel> 1 - to make the kernel mount in readonly mode. This can be overridden - by the use of the 'read-only' or 'read-write' keywords of the most - recent version of LILO. - -* Mount/umount package: This was recently posted to the net, and - implements the '-o remount' mount option which allows filesystems to - be remounted. Unlike the previous post, the version included here - also attempts to unmount the root filesystem on 'umount -a'. I have - also tried to clean up the man-pages. - -* fsck package: David Engel's fsck front-end. Read the README for it. - This package implements the 'fsck -A' command which will check all - filesystems in /etc/fstab automatically. - -Stephen Tweedie <sct@dcs.ed.ac.uk> |