fsirand8
Randomize inode generation numbers
Usage
fsirand [-b]
[-f]
[-p]
special
[special ...]
Overview
The fsirand utility installs random generation numbers on all the inodes for each file system specified on the command line by special. This increases the security of NFS-exported file systems by making it difficult to ``guess'' filehandles.
Note: newfs(8) now does the equivalent of fsirand itself so it is no longer necessary to run fsirand by hand on a new file system. It is only used to re-randomize or report on an existing file system.
The fsirand utility should only be used on an unmounted file system that has been checked with fsck(8) or a file system that is mounted read-only. The fsirand utility may be used on the root file system in single-user mode but the system should be rebooted via ``reboot -n'' afterwards.
Options
The available options are as follows:
-
-b -
Use the default block size (usually 512 bytes) instead of the value gleaned from the disklabel.
-
-f -
Force
fsirandto run even if the file system on special is not marked as clean. -
-p -
Print the current generation numbers for all inodes instead of generating new ones.
Caveats
Since fsirand allocates enough memory to hold all the inodes in a given cylinder group it may use a large amount of memory for large disks with few cylinder groups.
Releases
83 releases since FreeBSD 2.2.2-RELEASE; the text changed 42 times.