NAME
nisfiles — NIS+ database files and directory structure
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 stable 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/hostname
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
(nistbladm -D).
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
This file 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
This file contains the current cache of
NIS+
bindings being maintained by the cache manager.
The contents can be viewed with
nisshowcache(1M).
- hostname.log
This file 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.
- hostname.dict
This file is a dictionary that is used by the
NIS+
database to locate
its files.
It is created by the default
NIS+
database package.
- hostname.dict.log
This is the log file for the database dictionary.
When the server is checkpointed
(nisping -C),
this file will be deleted.
- hostname
This directory contains databases that the server uses.
- hostname/root.object
On root servers, this file contains a directory object that
describes the root of the name space.
- hostname/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.
- hostname/table_name
For each table in the directory there will be 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.
- hostname/table_name.log
This file 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
hostname/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
(see
nisping(1M))
operations periodically (such as, once a day)
to checkpoint the log file.
This can be done either through a
cron(1M)
job, or manually.
- hostname/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.
- hostname/cred.org_dir
This table contains the credentials of principals in this
NIS+
domain.
- hostname/groups_dir
This table contains the group authorization objects needed by
NIS+
to authorize group access.
- hostname/serving_list
This file 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.
AUTHOR
nisfiles
was developed by Sun Microsystems, Inc.
SEE ALSO
cp(1),
crontab(1),
mv(1),
rm(1),
nis+(1),
niscat(1),
nismatch(1),
nistbladm(1),
nisclient(1M),
nisinit(1M),
nislog(1M),
nisping(1M),
nis_db(3N),
nis_objects(3N).
