Selecting Your NIS-Compatible Domains

Make a list of your NIS clients and group them in their eventual NIS+ domains. If the NIS+ domain running in NIS-compatibility mode does not have the same name as its NIS clients' original NIS domain, you must change the NIS clients' domain name to the NIS+ domain name that is being supported by the NIS-compatible NIS+ server.

At first, NIS will no doubt be the primary service. As you become familiar with the intricacies of sharing information, you will be able to plan a transition to make NIS+ the primary service.

Some NIS+ users may want the capability of switching back and forth between the main NIS domain and the new NIS+ domain. The nisclient script can help them do this easily when backup files are made.

Determining NIS-Compatible Server Configuration

Take stock of your NIS servers, keeping in mind the requirements for your NIS+ servers. If you plan to eventually use them for the NIS+ service, upgrade them to the NIS+ recommendations. Identify which NIS servers will be used to support which NIS+ domains, and in what capacity (either master or replica). Remember that NIS+ servers belong to the domain above the one they support (except for the root domain servers). Since NIS+ servers do not belong to the domain they serve, you will not be able to use the same machines for other services that require domain-dependent information.

If possible, plan to use your NIS+ server machines only for NIS+. This arrangement could require you to transfer other network services, such as DNS name services, boot server, home directories, NFS servers, and so on, to non-NIS+ server machines.

At many sites, the NIS server plays multiple roles, such as NFS server, compute server, rlogin server, and mail host server. Because the NIS server uses the same information to resolve its names as do its clients, the NIS server can provide other services as well. As discussed in "The Domain Hierarchy" on page 12, except for root domains, all NIS+ servers live in the domain above the ones that they serve. So either do not run services on an NIS+ server that require access to the name service, or use other means, such as files in nsswitch.conf, to acquire this same information. This problem would be solved if there were no hierarchy, the NIS+ root servers would live in the

domain that they serve. The resource requirements of an NIS+ server are greater than those of an NIS server; therefore, it is advisable to not run other services along with NIS+.

If you have non-Solaris machines on your network, then either you can continue to run your NIS+ servers in NIS-compatibility mode or you can move all such machines into their own domain. If you move all non-Solaris machines to one subnet, you can remove the restriction of having NIS+ servers on the same subnet as their NIS-compatible clients require. This will reduce the number of replicas required for any domain.

Deciding How to Transfer Information Between Services

To keep information synchronized, be sure to make one namespace subordinate to the other. At first, the NIS namespace may be the dominant one, in which case you would make changes to the NIS maps and load them into the NIS+ tables. In effect, the NIS namespace would be the master database.

An NIS+ server in NIS-compatibility mode supports standard NIS maps. An exhaustive list of these maps is in the Notes section of the ypfiles(4) man page. But there are some limitations on map support: The NIS+ server serves ypmatch requests only on the netgroup map, and not on the reverse maps. It does not support enumeration requests (for example, ypcat). The passwd.adjunct map is not supported, either.

Eventually, the NIS+ namespace should be dominant. When that is the case, you would make changes in the NIS+ tables and copy them to the NIS maps.

The NIS+ nisaddent command and the NIS+ nispopulate script transfer information between NIS maps and NIS+ tables, as summarized in Table 4-1.

Table 4-1

NIS+ Command	Description
/usr/lib/nis/nisaddent -y	Transfers information from an NIS map to an NIS+ table after you run ypxfr to transfer maps from an NIS server to the local disk. Nonstandard NIS maps can be transferred to NIS+ tables if the information is in key-value pairs. Multicolumned maps will be not be transferred.
/usr/lib/nis/nisaddent -d	Copies information from an NIS+ table to a file, which can then be transferred to an NIS map with standard NIS utilities.
/usr/lib/nis/nispopulate -Y	Transfers information from NIS maps to NIS+ tables.

In versions of NIS+ previous to the Solaris 2.5 release it was necessary to use separate password commands (passwd, yppasswd, nispasswd) to handle password matters, depending on whether a user's password information was stored in /etc files, NIS maps, or NIS+ tables. Starting with the Solaris 2.5 release, all of these matters are handled automatically by the passwd or passwd -r nisplus commands and are controlled by the passwd entry in the user's nsswitch.conf file.

In order to properly implement the passwd command and password aging on your NIS+ or NIS-compatible network, the passwd entry of the nsswitch.conf file on every machine must be correct. This entry determines where the passwd command will go for password information and where it will update password information.

Only five passwd entry configurations are permitted:

Table 4-2 Permitted passwd nsswitch.conf Entries

passwd: files passwd: files nis passwd: files nisplus passwd: compat passwd_compat: nisplus

---

Caution - All of the nsswitch.conf files on all of your network's workstations must use one of the passwd configurations shown above. If you configure the passwd entry in any other way, users may not be able to log in.

---

In domains created with NIS-compatibility mode, the permissions are slightly different: permissions at the table level must be set to provide read rights to the world class, and at the column level permissions must provide read access to the nobody class.

Deciding How to Implement DNS Forwarding

NIS servers can forward DNS requests made from Solaris 1.x NIS clients. NIS+ servers running in NIS-compatibility mode also provide DNS forwarding, but only starting with the Solaris 2.3 or later releases. (This feature is available in the Solaris 2.2 release through a patch.) As a result, Solaris 2.x NIS clients must have appropriate /etc/nsswitch.conf and /etc/resolv.conf files installed locally.

Solaris 1.x NIS clients being supported by Solaris 2.0 or 2.1 servers running in NIS-compatibility mode will not be able to take advantage of DNS forwarding. You must upgrade those servers to Solaris 2.3 or later releases.

If the DNS domains are repartitioned, you must redefine new DNS zone files. Clients, however, may require updates to their /etc/resolv.conf file. A client, if it is also a DNS client, can set up its name service switch configuration file to search for host information in either DNS zone files or NIS maps--in addition to NIS+ tables.

DNS Forwarding for NIS+ Clients

NIS+ clients do not have implicit DNS-forwarding capabilities like NIS clients do. Instead, they take advantage of the name service switch. To provide DNS capabilities to an NIS+ client, change its hosts entry to:

hosts: nisplus dns [NOTFOUND=return] files

DNS Forwarding for Solaris 2.x NIS Clients

If an NIS client is using the DNS forwarding capability of an NIS-compatible NIS+ server, the client's nsswitch.conf file should not have the following syntax in the hosts file:

hosts: nis dns files # not for NIS clients

Since DNS-forwarding automatically forwards host requests to DNS, the syntax shown above would cause both the NIS+ server and the name service switch to forward unsuccessful requests to the DNS servers, slowing performance.

NIS and NIS+ Command Equivalents in the Solaris 1.x and 2.x Releases

The tables in this section give a quick overview of the differences between Solaris 1.x NIS commands, Solaris 2.x NIS commands, and their NIS+ equivalents.

• Table 4-3 on page 52 describes which NIS commands are supported in the Solaris 2.x release.
• Table 4-4 on page 53 and Table 4-5 on page 54 describe the NIS+ equivalents to NIS client and server commands in the Solaris 2.x release.
• Table 4-6 on page 55 contains a list of the NIS application programming interface functions and their NIS+ API equivalents, if they exist. See the appropriate man pages for details.

NIS Commands Supported in the Solaris 2.x Release

Only some NIS commands are supported in the Solaris 2.x release. NIS server commands are not shipped with the Solaris 2.x release. Just the NIS client commands are included. Whether these NIS commands run also depends on whether a Solaris 2.x NIS client is making requests of an NIS server or of an NIS+ server in NIS-compatibility mode. NIS clients cannot make updates to

NIS+ servers that are running in NIS-compatibility mode. For example, such clients cannot run the chkey and newkey commands. Table 4-3 lists the NIS commands supported in the Solaris 2.x release.

Table 4-3

Command Type	NIS Commands Supported in the Solaris 2.x Release	NIS Commands Not Supported in the Solaris 2.x Release
Utilities	ypinit ypxfr ypcat ypmatch yppasswd ypset ypwhich	yppush yppoll ypchsh ypchfn ypmake
Daemons	ypbind	ypserv ypxfrd rpc.ypupdated rpc.yppasswdd
NIS API	yp_get_default_domain() yp_bind() yp_unbind() yp_match() yp_first() yp_next() yp_all() yp_master() yperr_string() ypprot_err()	yp_order() yp_update()

Client and Server Command Equivalents

The two tables in this section contain NIS commands and their approximate NIS+ equivalents. The commands have been divided into two categories: Table 4-4 on page 53 contains name service client commands and Table 4-5 on page 54 contains name service server commands.

Client Command Equivalents

Table 4-4 on page 53 shows client-to-name server commands. These commands are typed on name service client machines and request information of name service servers. The commands in column 1 will run on Solaris 1.x or 2.x NIS clients connected to Solaris 1.x NIS servers. The commands in column 2 will run on Solaris 1.x or 2.x NIS clients connected to Solaris 2.x NIS+ servers running in NIS-compatibility mode. The commands in column 3 will only run on Solaris 2.x NIS+ clients connected to Solaris 2.x NIS+ servers. Commands are approximately equivalent across rows. "N/A" indicates that an equivalent command does not exist for that case.

Table 4-4 NIS Client Commands and Equivalent NIS+ Commands

SunOS 4.x NIS Server

NIS+ Server in

NIS- Compatibility Mode

NIS+ Server

ypwhich -m	ypwhich -m	niscat -o
ypcat	ypcat	niscat
ypwhich	ypwhich	N/A
ypmatch	ypmatch	nismatch/nisgre p
yppasswd	passwd	passwd
ypbind	ypbind	N/A
yppoll	N/A	N/A
ypset	ypset	N/A
N/A	ypinit -c	nisclient -c

Note that:

• In the Solaris 2.5 release, the passwd command should be used regardless of NIS or NIS+ status. The functions previously performed by nispasswd and yppasswd have now been included in the passwd command.
• The ypinit -c command is available only on Solaris 2.x NIS clients.
• The ypcat command is not supported for queries directed to the netgroup table. The NIS client's request will time out before an answer is received because this table's format is so different from the netgroup NIS map's format.

Server Command Equivalents

Table 4-5 on page 54 shows name server-to-name server commands. The NIS server commands are not included in the Solaris 2.x release, so they are not available to either NIS+ servers or NIS+ servers in NIS-compatibility mode. In addition, an NIS server cannot make updates to an NIS+ server, nor can an NIS+ server make updates to an NIS server. Column 3 lists the NIS+ server commands that are equivalent to the NIS server commands in column 1. There are no exact equivalents for servers in NIS-compatibility mode because NIS-compatibility mode refers only to client commands.

Table 4-5

SunOS 4.x NIS Server	NIS+ Server in NIS-Compatibility Mode	NIS+ Server
ypxfr	N/A	N/A
makedbm	N/A	nisaddent
ypinit -m ypinit -s	N/A	nisserver
ypserv	rpc.nisd -Y	rpc.nisd
ypserv -d	rpc.nisd -Y -B	no DNS forwarding needed; use /etc/nsswitch.conf
ypxfrd	N/A	N/A
rpc.ypupdated	N/A	N/A
rpc.yppasswd	rpc.nispasswdd	rpc.nispasswdd

Table 4-5 (Continued)

SunOS 4.x NIS Server	NIS+ Server in NIS-Compatibility Mode	NIS+ Server
yppush	N/A	nisping
ypmake	N/A	nissetup, nisaddent
ypxfr	N/A	N/A

NIS and NIS+ API Function Equivalents

To completely convert your site to NIS+, you must both change the name service and port all applications to NIS+. Any internally created applications that make NIS calls have to be modified to use NIS+ calls. Otherwise, you will always have to run your NIS+ servers in NIS-compatibility mode, with all the drawbacks that this mode entails. External applications may force you to run your namespace in NIS-compatibility mode until they are updated as well.

Table 4-6 contains a list of the NIS API functions and their NIS+ API equivalents, if they exist.

Table 4-6

NIS API Functions	NIS+ API Functions
yp_get_default_domain ()	nis_local_directory()
ypbind()	N/A
ypunbind()	N/A
ypmatch()	nis_list()
yp_first()	nis_first_entry()
yp_next()	nis_next_entry()
yp_all()	nis_list()
yp_master()	nis_lookup()
yperr_string()	nis_perror() nis_sperrno()

Table 4-6 (Continued)

NIS API Functions	NIS+ API Functions
ypprot_err()	nis_perror() nis_sperrno()
yp_order()	N/A
yp_update()	nis_add_entry(), nis_remove_entry(), nis_modify_entry()

NIS-Compatibility Mode Protocol Support

Table 4-7 shows which NIS protocols are supported by NIS+ servers in NIS-compatibility mode.

Table 4-7

NIS Protocols	Compatibility Description
NIS client V2 protocol	Supported
NIS server-to- server protocol	Unsupported
NIS client update protocol	yppasswd protocol supported
NIS client V1 protocol	Not supported except for YPPROC_NULL, YPPROC_DOMAIN, and YPPROC_DOMAIN_NONACK