/sbin : Essential system binaries

Linux systems place these additional files into /sbin.

• Second extended filesystem commands (optional):

  • badblocks

  • dumpe2fs

  • e2fsck

  • mke2fs

  • mklost+found

  • tune2fs

• Boot-loader map installer (optional):

  • lilo

Optional files for /sbin:

• Static binaries:

  • ldconfig

  • sln

  • ssync

  Static ln (sln) and static sync (ssync) are useful when things go wrong. The primary use of sln (to repair incorrect symlinks in /lib after a poorly orchestrated upgrade) is no longer a major concern now that the ldconfig program (usually located in /usr/sbin) exists and can act as a guiding hand in upgrading the dynamic libraries. Static sync is useful in some emergency situations. Note that these need not be statically linked versions of the standard ln and sync, but may be.

  The ldconfig binary is optional for /sbin since a site may choose to run ldconfig at boot time, rather than only when upgrading the shared libraries. (It's not clear whether or not it is advantageous to run ldconfig on each boot.) Even so, some people like ldconfig around for the following (all too common) situation:

  1. I've just removed /lib/<file>.

  2. I can't find out the name of the library because ls is dynamically linked, I'm using a shell that doesn't have ls built-in, and I don't know about using "echo *" as a replacement.

  3. I have a static sln, but I don't know what to call the link.

• Miscellaneous:

  • ctrlaltdel

  • kbdrate

  So as to cope with the fact that some keyboards come up with such a high repeat rate as to be unusable, kbdrate may be installed in /sbin on some systems.

  Since the default action in the kernel for the Ctrl-Alt-Del key combination is an instant hard reboot, it is generally advisable to disable the behavior before mounting the root filesystem in read-write mode. Some init suites are able to disable Ctrl-Alt-Del, but others may require the ctrlaltdel program, which may be installed in /sbin on those systems.