mkfs" -- Command" "

//eettcc//mmkkffss [[--bb _b_o_o_t]] [[--dd]] [[--ff _n_a_m_e]] [[--ii _i_n_o_d_e_s]] [[--mm _a_r_g]] [[--nn _a_r_g]] [[--pp _p_a_c_k]] _f_i_l_e_s_y_s_t_e_m _p_r_o_t_o

If proto is a number, mkfs creates an empty file system (containing only a root directory) of the size in blocks given by proto. The number of i-nodes is calculated as a percentage of this number. The command

     /etc/mkfs /dev/fha0 2400

creates a file system on a high-density, 5.25-inch diskette in drive 0. If the disk is a high-density, 3.5-inch diskette, use the command:

     /etc/mkfs /dev/fva0 2880

If proto is a file name, however, the contents of that file will be used as a prototype for modeling the new file system. This prototype file must be laid out in the following manner:

_b_o_o_t_s_t_r_a_p___f_i_l_e___n_a_m_e  _f_i_l_e___s_y_s_t_e_m___n_a_m_e  _d_e_v_i_c_e___n_a_m_e
_n_o_.___o_f___b_l_o_c_k_s  _n_o_.___o_f___i_-_n_o_d_e_s  _n   _m
_%_b _X_X _X_X _X_X
...
_d_i_r_e_c_t_o_r_y___n_a_m_e
     _d_i_r_e_c_t_o_r_y___n_a_m_e _m_o_d_e _u_s_e_r___i_d _g_r_o_u_p___i_d _c_o_n_t_e_n_t_s
     ...
     $
$

Each line is described below.

The first line has three fields. Field 1, bootstrap_file_name, contains the name of a file that holds the boot strap, which must fit into block 0 of the disk. Field 2, file_system_name, gives the name of the file system; and field 3, device_name, gives the name of file system's physical device (for example, //ddeevv//hhdd11). Only the first six characters in field 2 and the first 11 in field 3 are significant; all characters after them are ignored.

The second line contains four fields. Field 1, no._of_blocks, gives the size of the file system in blocks; field 2, no_of_i-nodes, gives the number of i-nodes in the file system. Because each file or directory requires one i-node, this number represents the limit on the number of files that may be created in the file system. A ratio of seven blocks per i- node generally works well.

Fields 3 and 4 control free list interleaving on your disk. n is the size of a ``virtual cylinder'': fsck allocates all the blocks on one virtual cylinder before it advances to the next virtual cylinder. The value of n must be less than or equal to 255, and should evenly divide the actual size of a cylinder on the device. m tells the system how many blocks to skip each time it increments a free list block number, i.e., the free list ``interleave''; n mod m must be zero. Choosing an optimal interleave value may improve system performance for the device. The optimal values for n and m are hardware- specific and can be determined by experimentation.

Next, the third line and following begin with %%bb. These list the bad blocks on your storage device. One or more block numbers may appear on each line, separated by white space. These blocks are allocated to the bad block file (i- node 1).

The remaining lines in the _p_r_o_t_o file define the names, modes, and contents of the directories and files in the file system. These lines are divided into fields separated by white space (blanks or tabs) as follows:

+o

The first field names the file or directory to be created. This field is missing on the first line, which describes the root directory of the file system.

+o

The second field describes the mode of the file, which is six characters long. The first character gives the file type, that is, whether the file is ordinary (`-'), directory (`d'), block special (`b'), or character special (`c'). The second character is `u' for set user id on execution, and `-' otherwise. The third character is `g' for set group id on execution, and `-' otherwise. Characters 4 through 6 specify permissions in octal; for example, 664444 specifies read and write permission for the owner, read permission for other users from the same group, and read permission for users from other groups. If the above file type were a directory, subsequent files are recursively defined under that directory, until the current level of directory is terminated by a line containing a `$' character.

+o

The next two fields specify the owner's numerical user id and group id.

+o

The last field describes file contents. For a directory, it is not needed. For an ordinary file, it is the name of a COHERENT file that will be copied into the newly created file. For block or character-special files, there are two fields that specify the numbers of the major and minor devices.

The proto file need not contain all of the above fields. However, it must contain the name of the boot block (line 1), the number of blocks and the number of i-nodes (line 2), the list of bad blocks, the name of at least one directory, and the dollar sign that ends the file.

Command-line Options

--bb _b_o_o_t

Specifies the file to use as the ``bootstrap'' for the file system.

--dd

Preserve file dates and times on the new file system.

--ff _n_a_m_e

Label the file system with the given _n_a_m_e. _n_a_m_e must be less than seven characters in length.

--ii _i_n_o_d_e_s

Use _i_n_o_d_e_s as the number of inodes for the file system.

--mm _a_r_g

Set the number of blocks to skip when incrementing virtual block number. This is the same as the _m option as set on line 2 of the prototype file. You can use this option if you choose not to use a prototype file.

--nn _a_r_g

Set the size of a ``virtual cylinder''. This is the same as the _n option as set on line 2 of the prototype file. You can use this option if you choose not to use a prototype file.

--pp _p_a_c_k

Set the file system ``pack name'' to _p_a_c_k. _p_a_c_k must be less than seven characters in length.

Example

/conf/boot.fha
2400 100
%b 55
%b 185 86
d--755 3 1
     coherent ---644 3 1 /coherent
     tmp     d--777 3 1
     $
     bin     d--755 3 1
             mail   -u-755 0 1 /bin/mail
     $
     dev     d--755 3 1
             tty30  c--644 0 1 3 0
             tty35  c--644 0 1 3 5
             mt0    b--600 0 1 12 0
     $
$

You can use the command badscan to draw up the list of bad blocks on your disk and create a skeleton _p_r_o_t_o file.

See Also

• badscan,
• chmod,
• commands,
• fsck,
• mount,
• restor
A

Notes

     su root
     for i in `from 1 to 500`
     do
          touch /lost+found/$i
     done
     rm /lost+found/*

A Run this script for each file system whose lost+found directory you wish to expand. For example, if you have a file system mount on directory /u, run this script for directory /u/lost+found instead of for /lost+found.