NIS-to-LDAP Service Overview
The NIS–to–LDAP transition service (N2L service) replaces existing NIS daemons on the NIS master server
with NIS–to–LDAP transition daemons. The N2L service also creates an NIS–to–LDAP mapping file
on that server. The mapping file specifies the mapping between NIS map entries
and equivalent Directory Information Tree (DIT) entries in LDAP. An NIS master server
that has gone through this transition is referred to as an N2L server. The slave
servers do not have an NISLDAPmapping file, so they continue to function in
the usual manner. The slave servers periodically update their data from the N2L
server as if it were a regular NIS master.
The behavior of the N2L service is controlled by the ypserv and
NISLDAPmapping configuration files. A script, inityp2l, assists with the initial setup of these
configuration files. Once the N2L server has been established, you can maintain N2L
by directly editing the configuration files.
The N2L service supports the following:
In any naming system, only one source of information can be the
authoritative source. In traditional NIS, NIS sources are the authoritative information. When using the
N2L service, the source of authoritative data is the LDAP directory. The directory
is managed by using directory management tools, as described in Chapter 9, LDAP Basic Components and Concepts (Overview).
NIS sources are retained for emergency backup or backout only. After using the
N2L service, you can gradually phase out NIS clients. Eventually, all NIS clients
can be replaced by Solaris LDAP naming services clients.
Additional overview information is provided in the following subsections:
NIS-to-LDAP Tools and the Service Management Facility
The NIS and LDAP services are managed by the Service Management Facility. Administrative
actions on these services, such as enabling, disabling, or restarting, can be performed
by using the svcadm command. You can query the status of services by
using the svcs command. For more information about using SMF with LDAP and
NIS, see LDAP and the Service Management Facility and NIS and the Service Management Facility. For an overview of SMF, refer to Chapter 16, Managing Services (Overview), in System Administration Guide: Basic Administration.
Also refer to the svcadm(1M) and svcs(1) man pages for more details.
NIS-to-LDAP Audience Assumptions
You need to be familiar with NIS and LDAP concepts, terminology, and IDs
to perform the procedures in this chapter. For more information about the NIS
and LDAP naming services, see the following sections of this book.
When Not to Use the NIS-to-LDAP Service
Do not use the N2L service in these situations:
In an environment where there is no plan to share data between NIS and LDAP naming services clients
In such an environment, an N2L server would serve as an excessively complex NIS master server.
In an environment where NIS maps are managed by tools that modify the NIS source files (other than yppasswd)
Regeneration of NIS sources from DIT maps is an imprecise task that requires manual checking of the resulting maps. Once the N2L service is used, regeneration of NIS sources is provided only for backout or reverting to NIS.
In an environment with no NIS clients
In such an environment, use Solaris LDAP naming services clients and their corresponding tools.
Effects of the NIS-to-LDAP Service on Users
Simply installing the files that are related to the N2L service does not
change the NIS server's default behavior. At installation, the administrator will see some
changes to NIS man pages and the addition of N2L helper scripts,
inityp2l and ypmap2src, on the servers. But as long as inityp2l is not
run or the N2L configuration files are not created manually on the NIS
server, the NIS components continue to start in traditional NIS mode and function
as usual.
After inityp2l is run, users see some changes in server and client behavior.
Following is a list of NIS and LDAP user types and a description
of what each type of user should notice after the N2L service is
deployed.
User Type |
Effect of N2L Service |
|---|
NIS master server administrators |
The NIS master server is
converted to an N2L server. The NISLDAPmapping and ypserv configuration files are
installed on the N2L server. After the N2L server is established, you can
use LDAP commands to administer your naming information. |
NIS slave server administrators |
After the
N2L transition, an NIS slave server continues to run NIS in the usual
manner. The N2L server pushes updated NIS maps to the slave server when
yppush is called by ypmake. See the ypmake(1M) man page. |
NIS clients |
NIS read operations are
no different than traditional NIS. When a Solaris LDAP naming services client changes
information in the DIT, the information is copied into the NIS maps. The
copy operation is complete after a configurable timeout expires. Such behavior is similar
to the behavior of a normal NIS client when the client is connected
to an NIS slave server. If an N2L server cannot bind to the
LDAP server for a read, the N2L server returns the information from its
own cached copy. Alternatively, the N2L server can return an internal server error.
You can configure the N2L server to respond either way. See the ypserv(1M)
man page for more details. |
All users |
When an NIS client makes a password
change request, the change is immediately visible on the N2L master server and
to native LDAP clients. If you attempt to change a password on the
NIS client, and the LDAP server is unavailable, then the change is refused
and the N2L server returns an internal server error. This behavior prevents incorrect
information from being written into the cache. |
NIS-to-LDAP Transition Terminology
The following terms are related to the implementation of the N2L service.
Table 15-1 Terminology Related to the N2L Transition
Term |
Description |
|---|
N2L
configuration files |
The /var/yp/NISLDAPmapping and /var/yp/ypserv files that the ypserv daemon uses to
start the master server in N2L mode. See the NISLDAPmapping(4) and ypserv(4) man pages
for details. |
map |
In the context of the N2L service, the term map is
used in two ways:
|
mapping |
The process of converting NIS entries to or from
LDAP DIT entries. |
mapping file |
The NISLDAPmapping file that establishes how to map entries between
NIS and LDAP files. |
standard maps |
Commonly used NIS maps that are supported
by the N2L service without requiring manual modification to the mapping file. A
list of supported standard maps is provided in Supported Standard Mappings. |
nonstandard maps |
Standard NIS maps that
are customized to use mappings between NIS and the LDAP DIT other than
the mappings identified in RFC 2307 or its successor. |
custom map |
Any map that
is not a standard map and therefore requires manual modifications to the mapping
file when transitioning from NIS to LDAP. |
LDAP client |
Any traditional LDAP client that
reads and writes to any LDAP server. A traditional LDAP client is a
system that reads and writes to any LDAP server. A Solaris LDAP naming
services client handles a customized subset of naming information. |
LDAP naming services client |
A Solaris
LDAP client that handles a customized subset of naming information. |
N2L server |
An NIS
master server that has been reconfigured as an N2L server by using the
N2L service. Reconfiguration includes replacing NIS daemons and adding new configuration files. |
NIS-to-LDAP Commands, Files, and Maps
There are two utilities, two configuration files, and a mapping that are associated
with the N2L transition.
Table 15-2 Descriptions of N2L Commands, Files, and Maps
Command/File/Map |
Description |
|---|
/usr/lib/netsvc/yp/inityp2l |
A utility that assists with the creation of the
NISLDAPmapping and ypserv configuration files. This utility is not a general-purpose tool for
the management of these files. An advanced user can maintain the N2L configuration
files or create custom mappings by using a text editor to examine and
customize the inityp2l output. See the inityp2l(1M) man page. |
/usr/lib/netsvc/yp/ypmap2src |
A utility that converts standard NIS
maps to approximations of the equivalent NIS source files. The primary use for
ypmap2src is to convert from an N2L transition server to traditional NIS.
See the ypmap2src(1M) man page. |
/var/yp/NISLDAPmapping |
A configuration file that specifies the mapping between
NIS map entries and equivalent Directory Information Tree (DIT) entries in LDAP. See the
NISLDAPmapping(4) man page. |
/var/yp/ypserv |
A file that specifies configuration information for the NIS–to–LDAP transition daemons. See
the ypserv(4) man page. |
ageing.byname |
A mapping used by yppasswdd to read and write password aging
information to the DIT when the NIS-to-LDAP transition is implemented. |
Supported Standard Mappings
By default, the N2L service supports mappings between the following list of maps
and RFC 2307, or its successors', LDAP entries. These standard maps do not
require manual modification to the mapping file. Any maps on your system that
are not in the following list are considered custom maps and require manual
modification.
The N2L service also supports automatic mapping of the auto.* maps. However, since
most auto.* file names and contents are specific to each network configuration, those
files are not specified in this list. The exceptions to this are the
auto.home and auto.master maps, which are supported as standard maps.
audit_user
auth_attr
auto.home
auto.master
bootparams
ethers.byaddr ethers.byname
exec_attr
group.bygid group.byname group.adjunct.byname
hosts.byaddr hosts.byname
ipnodes.byaddr ipnodes.byname
mail.byaddr mail.aliases
netgroup netgroup.byprojid netgroup.byuser netgroup.byhost
netid.byname
netmasks.byaddr
networks.byaddr networks.byname
passwd.byname passwd.byuid passwd.adjunct.byname
printers.conf.byname
prof_attr
project.byname project.byprojectid
protocols.byname protocols.bynumber
publickey.byname
rpc.bynumber
services.byname services.byservicename
timezone.byname
user_attr
During the NIS-to-LDAP transition, the yppasswdd daemon uses the N2L-specific map, ageing.byname, to
read and write password aging information to the DIT. If you are not
using password aging, then the ageing.byname mapping is ignored.
