Linux nistbladm command
On the Solaris operating system, the nistbladm command is used to perform NIS+ table administration functions.
Description
The nistbladm command is used to administer NIS+ tables. There are five primary operations that it performs: creating and deleting tables, adding entries to tables, modifying entries within tables, and removing entries from tables.
Though NIS+ does not place restrictions on the size of tables or entries, the size of data has an impact on the performance and the disk space requirements of the NIS+ server. NIS+ is not designed to store huge pieces of data, such as files; instead, pointers to files should be stored in NIS+.
NIS+ design is optimized to support 10,000 objects with a total size of 10 megabytes. If the requirements exceed the above, it is suggested that the domain hierarchy be created, or the data stored in the tables be pointers to the actual data, instead of the data itself.
When creating tables, a table type, type, and a list of column definitions must be provided.
type is a string that is stored in the table and later used by the service to verify that entries being added to it are of the correct type.
Syntax for column definitions is:
colname=[flags][,access]
flags is a combination of:
| S | Searchable. Specifies that searches can be done on the column's values (see nismatch). |
| I | Case-insensitive (only makes sense in combination with S). Specifies that searches should ignore case. |
| C | Crypt. Specifies that the column's values should be encrypted. |
| B | Binary data (does not make sense in combination with S). If not set, the column's values are expected to be null terminated ASCII strings. |
| X | XDR encoded data (only makes sense in combination with B). |
access is specified in the format as defined by the nischmod command.
When manipulating entries, this command takes two forms of entry name. The first uses several space separated colname=value pairs that specify column values in the entry. The second is an NIS+ indexed name, indexedname, of the form:
[ colname=value, ... ],tablename
Syntax
nistbladm -a | -A [-D defaults] colname = value... tablename
nistbladm -a | -A [-D defaults] indexedname
nistbladm -c [-D defaults] [-p path] [-s sep] type colname = [flags]
[, access]... tablename
nistbladm -d tablename
nistbladm -e | -E colname = value... indexedname
nistbladm -m colname = value... indexedname
nistbladm -r | -R [colname = value...] tablename
nistbladm -r | -R indexedname
nistbladm -u [-p path] [-s sep] [-t type] [colname = access...] tablename
Options
The following options are supported by nistbladm:
| -a | A | Adds entries to an NIS+ table. The difference between the lowercase 'a' and the uppercase 'A' is in the treatment of preexisting entries. The entry's contents are specified by the column=value pairs on the command line. Values for all columns must be specified when adding entries to a table. Normally, NIS+ reports an error if an attempt is made to add an entry to a table that would overwrite an entry that already exists. This prevents multiple parties from adding duplicate entries and having one of them get overwritten. To force the add, the uppercase 'A' specifies that the entry is to be added, even if it already exists. This option is analogous to a modify operation on the entry. |
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| -c | Creates a table named tablename in the namespace. The table that is created must have at least one column and at least one column must be searchable. | ||||||||
| -d tablename | Destroys the table named tablename. The table that is being destroyed must be empty. The table's contents can be deleted with the -R option below. | ||||||||
| -e | E | Edits the entry in the table that is specified by indexdname. The indexdname must uniquely identify a single entry. It is possible to edit the value in a column that would change the indexed name of an entry. The change (colname=value) may affect other entries in the table if the change results in an entry whose indexed name is different from indexedname and which matches that of another existing entry. In this case, the -e option fails and an error is reported. The -E option forces the replacement of the existing entry by the new entry (effectively removing two old entries and adding a new one). |
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| -m | A synonym for -E. This option is superseded by the -E option. | ||||||||
| -r | R | Removes entries from a table. The xentry is specified by either several column=value pairs on the command line, or an indexed name that is specified as entryname. The difference between the interpretation of the lowercase 'r' versus the uppercase 'R' is in the treatment of non-unique entry specifications. Normally the NIS+ server disallows an attempt to remove an entry when the search criterion specified for that entry resolves to more than one entry in the table. However, it is sometimes desirable to remove more than one entry, as when you are attempting to remove all the entries from a table. In this case, using the uppercase 'R' forces the NIS+ server to remove all entries matching the passed search criterion. If that criterion is null and no column values specified, all entries in the table are removed. | ||||||||
| -u | Updates attributes of a table. This option allows the concatenation path (-p), separation character (specified with the (-s)), column access rights, and table type string (-t) of a table to be changed. Neither the number of columns, nor the columns that are searchable may be changed. | ||||||||
| -D defaults | When creating objects, this option specifies a different set of defaults to be used during this operation. The defaults string is several tokens separated by colons. These tokens represent the default values to be used for the generic object properties. All of the legal tokens are described below:
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| -p path | When creating or updating a table, this option specifies the table's search path. When an nis_list() function is invoked, the user can specify the flag FOLLOW_PATH to tell the client library to continue searching tables in the table's path if the search criteria used does not yield any entries. The path consists of an ordered list of table names, separated by colons. The names in the path must be fully qualified. | ||||||||
| -s sep | When creating or updating a table, this option specifies the table's separator character. The separator character is used by niscat when displaying tables on the standard output. Its purpose is to separate column data when the table is in ASCII form. The default value is a space. | ||||||||
| -t type | When updating a table, this option specifies the table's type string. |
Environment
nistbladm makes use of the following environment variables:
| NIS_DEFAULTS | This variable contains a defaults string that overrides the NIS+ standard defaults. If the -D switch is used, those values then override both the NIS_DEFAULTS variable and the standard defaults. |
| NIS_PATH | If this variable is set, and the NIS+ table name is not fully qualified, each directory specified is searched until the table is found. |
Examples
nistbladm -m name=robert [name=bob],hobbies
Modify the entry named bob, changing the name to robert.
Related commands
niscat — Display NIS+ tables and objects.
nischmod — Change access rights on an NIS+ object.
nischown — Change the owner of an NIS+ object on a system running Solaris.
nischttl — Change the time to live value of an NIS+ object.
nisdefaults — Display NIS+ default values.
nismatch — Utilities for searching NIS+ tables.