NAME

ofstab − optical file system mounting table

SYNOPSIS

/etc/ofstab

DESCRIPTION

The file /etc/ofstab contains entries for optical file systems to mount using the omount(8) command, which is normally invoked by the /etc/rc.local script at system startup time. 

Each entry consists of a line of the form:

device   directory   label   options

device is the pathname of a character-special device node referencing the ofs pseudo-device driver (see ofs(4)).

directory is the pathname of the directory on which to mount the file system. 

label is an optional identifier for the file system.  label should be a single word (or a string enclosed in quotes) not over 20 characters long.  omount uses label to verify the identity of the file system. 

options represents a space-separated list of mounting options in the form accepted by omount.  Several options may be combined into a single word, but each option word must be introduced by a hyphen. 

−a Do not mount this file system automatically (using omount −a). 

−g Create files with BSD semantics for propagation of the group ID.  With this option, files inherit the group ID of the directory in which they are created, regardless of the value of the directory’s set-GID bit. 

−l The following value is the file buffer length in blocks.  To optimize access latency, physical data transfers to and from the optical storage media are accumulated and performed several blocks at a time.  This parameter may be varied to take optimal advantage of the characteristics of various optical disk drives.  The default buffer length is 96 kilobytes. 

−m Do not permit other file systems to be mounted on directory nodes within this file system. 

−p The following value is the free space padding allowance in blocks per thousand.  If less than this amount of space remains on the volume, only the super-user may create files.  The default padding allowance is one block per thousand. 

−q The following value is the maximum number of contiguous errors accepted without producing a fatal I/O fault.  If this value is zero, no error quota is imposed.  The default error quota is 24. 

−r Read-only — Mount this file system read-only.  Physically write-protected volumes are always mounted read-only, whether or not this option is specified. 

−s Slow mount — Access every file index record when mounting this file system.  The normal fast-mount sequence locates file index records using a vector list.  If any record cannot be read, the corresponding file cannot be accessed.  Using the slow-mount option allows a previous version of a file index record to be identified. 

−t The following value is the buffer flush time in seconds.  Due to the write-once nature of optical file storage media, the ofs daemon attempts to maximize media utilization by keeping recent updates to a file in memory until the file is closed or flushed.  However, to minimize memory usage and to insure that files remain reasonably current, a memory residence time limit is observed.  If no access occurs to a file on the file system within this time, any pending updates will be posted to the optical medium and the memory buffer space occupied will be released for other uses.  The default value of this parameter is one minute.  If a value of zero is supplied, no time limit is imposed, and file updates may remain pending indefinitely, or until the file system is demounted. 

−x Do not permit set-UID execution of programs on this file system. 

A pound-sign (#) as the first character of a word identifies the rest of that line as a comment to be ignored by omount. 

/etc/ofstab is only read by omount, and not written; it is the duty of the system administrator to properly create and maintain this file. 

The order of records in /etc/ofstab is important because omount processes the file sequentially; the entry for a file system must appear before the entries for any file systems to be mounted within it. 

FILES

/etc/ofstab

SEE ALSO

ofs(4), omount(8)

  —  30 September 1989