man Pages(4): File Formats

nisfiles(4)

NAME | SYNOPSIS | DESCRIPTION | SEE ALSO

NAME

nisfiles- NIS+ database files and directory structure

SYNOPSIS

/var/nis

DESCRIPTION

The Network Information Service Plus (NIS+) uses a memory based, replicated database. This database uses a set of files in the /var/nis directory for checkpointing to table storage and for maintaining a transaction log. Additionally, the NIS+ server and client use files in this directory to store binding and state information.

The NIS+ service implements an authentication and authorization system that is built upon Secure RPC. In this implementation, the service uses a table named cred.org_dir.domain-name to store the public and private keys of principals that are authorized to access the NIS+ namespace. It stores group access information in the subdomain groups_dir.domain-name as group objects. These two tables appear as files in the /var/nis/data directory on the NIS+ server.

Unlike the previous versions of the network information service, in NIS+, the information in the tables is initially loaded into the service from the ASCII files on the server and then updated using NIS+ utilities (see nistbladm(1)). Some sites may wish to periodically regenerate the ASCII files for archival purposes. To do this, a script should be added in the crontab(1) of the server that lists these tables and creates the ASCII file from the result.

Note: Except for the NIS_COLDSTART and NIS_SHARED_DIRCACHE file, no other files should be manipulated by commands such as cp(1), mv(1) or rm(1). The transaction log file keeps logs of all changes made, and hence the files cannot be manipulated independently.

The files described below are stored in the /var/nis directory:

NIS_COLDSTART

Contains NIS+ directory objects that are to be preloaded into the NIS+ cache at startup time. This file is usually created at NIS+ installation time. See nisinit(1M) or nisclient(1M).

NIS_SHARED_DIRCACHE

Contains the current cache of NIS+ bindings being maintained by the cache manager. The contents can be viewed with nisshowcache(1M).

client_info

Contains configuration information (preferred servers, options, etc.) for nis_cachemgr(1M) and (potentially) other NIS+ clients on the system. It is manipulated by the nisprefadm(1M) command.

.pref_servers

A cached copy of preferred server information. It is maintained by nis_cachemgr. Do not edit this file manually.

trans.log

Contains a transaction log that is maintained by the NIS+ service. It can be viewed using the nislog(1M) command. This file contains holes. Its apparent size may be a lot higher than its actual size. There is only one transaction log per server.

data.dict

A dictionary that is used by the NIS+ database to locate its files. It is created by the default NIS+ database package.

data.dict.log

The log file for the database dictionary. When the server is checkpointed (see the -C option of nisping(1M)), this file will be deleted.

data

Contains databases that the server uses.

data/root.object

On root servers, this file contains a directory object that describes the root of the name space.

data/parent.object

On root servers, this file contains a directory object that describes the parent namespace. This file is created by the nisinit(1M) command.

data/table_name

For each table in the directory there is a file with the same name that stores the information about that table. If there are subdirectories within this directory, the database for the table is stored in the file, table_name.subdirectory.

data/table_name.log

Contains the database log for the table table_name. The log file maintains the state of individual transactions to each database. When a database has been checkpointed (that is, all changes have been made to the data/table_name stable storage), this log file will be deleted.

Currently, NIS+ does not automatically do checkpointing. The system administrator may want to do nisping-C operations periodically (such as, once a day) to checkpoint the log file. This can be done either through a cron(1M) job, or manually.

data/root_dir

On root servers, this file stores the database associated with the root directory. It is similar to other table databases. The corresponding log file is called root_dir.log.

data/cred.org_dir

Table containing the credentials of principals in this NIS+ domain.

data/groups_dir

Table containing the group authorization objects needed by NIS+ to authorize group access.

data/serving_list

Contains a list of all NIS+ directories that are being served by the NIS+ server on this server. When this server is added or deleted from any NIS+ directory object, this file is updated by the server.