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Use <acronym role=".."> tag with the first three occurrences of NFS,

Browse source 
NIS, NTP, and remove other instances of <acronym role=".."> for
subsequent uses of the acronym.

The consensus seems to be that a few underlines for these acronyms
with mouseover definitions is good, but it gets distracting if we
every single instance as a faint dotted underline.
This commit is contained in:
Murray Stokely 2004-07-22 03:03:38 +00:00
parent 6dfe5db2ed
commit 1b9b4d4a5b
Notes: svn2git 2020-12-08 03:00:23 +00:00 
svn path=/head/; revision=21611
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en_US.ISO8859-1/books/handbook/network-servers/chapter.sgml
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@ -536,9 +536,11 @@ server-program-arguments</programlisting>
<indexterm><primary>NFS</primary></indexterm> <indexterm><primary>NFS</primary></indexterm>
<para>Among the many different filesystems that FreeBSD supports is <para>Among the many different filesystems that FreeBSD supports is
the Network File System, also known as <acronym>NFS</acronym>. the Network File System, also known as <acronym role="Network
<acronym>NFS</acronym> allows a system to share directories and files File System">NFS</acronym>.
with others over a network. By using <acronym>NFS</acronym>, users and <acronym role="Network File System">NFS</acronym> allows a system to share directories and files
with others over a network. By using <acronym role="Network
File System">NFS</acronym>, users and
programs can access files on remote systems almost as if they were local programs can access files on remote systems almost as if they were local
files.</para> files.</para>
@ -1088,14 +1090,15 @@ Exports list on foobar:
<indexterm><primary>Linux</primary></indexterm> <indexterm><primary>Linux</primary></indexterm>
<indexterm><primary>NetBSD</primary></indexterm> <indexterm><primary>NetBSD</primary></indexterm>
<indexterm><primary>OpenBSD</primary></indexterm> <indexterm><primary>OpenBSD</primary></indexterm>
<para>&nis;, which stands for Network Information Services, was <para><acronym role="Network Information System">NIS</acronym>, which stands for Network Information Services, was
developed by Sun Microsystems to centralize administration of &unix; developed by Sun Microsystems to centralize administration of &unix;
(originally &sunos;) systems. It has now essentially become an (originally &sunos;) systems. It has now essentially become an
industry standard; all major &unix; like systems (&solaris;, HP-UX, &aix;, Linux, industry standard; all major &unix; like systems (&solaris;, HP-UX, &aix;, Linux,
NetBSD, OpenBSD, FreeBSD, etc) support &nis;.</para> NetBSD, OpenBSD, FreeBSD, etc) support <acronym role="Network
Information System">NIS</acronym>.</para>
<indexterm><primary>yellow pages</primary><see>NIS</see></indexterm> <indexterm><primary>yellow pages</primary><see>NIS</see></indexterm>
<para>&nis; was formerly known as Yellow Pages, but because of <para><acronym role="Network Information System">NIS</acronym> was formerly known as Yellow Pages, but because of
trademark issues, Sun changed the name. The old term (and yp) is trademark issues, Sun changed the name. The old term (and yp) is
still often seen and used.</para> still often seen and used.</para>
@ -1104,9 +1107,9 @@ Exports list on foobar:
<secondary>domains</secondary> <secondary>domains</secondary>
</indexterm> </indexterm>
<para>It is a RPC-based client/server system that allows a group <para>It is a RPC-based client/server system that allows a group
of machines within an &nis; domain to share a common set of of machines within an NIS domain to share a common set of
configuration files. This permits a system administrator to set configuration files. This permits a system administrator to set
up &nis; client systems with only minimal configuration data and up NIS client systems with only minimal configuration data and
add, remove or modify configuration data from a single add, remove or modify configuration data from a single
location.</para> location.</para>
@ -1121,8 +1124,8 @@ Exports list on foobar:
<para>There are several terms and several important user processes <para>There are several terms and several important user processes
that you will come across when that you will come across when
attempting to implement &nis; on FreeBSD, whether you are trying to attempting to implement NIS on FreeBSD, whether you are trying to
create an &nis; server or act as an &nis; client:</para> create an NIS server or act as an NIS client:</para>
<indexterm> <indexterm>
<primary><application>portmap</application></primary> <primary><application>portmap</application></primary>
@ -1141,38 +1144,38 @@ Exports list on foobar:
</thead> </thead>
<tbody> <tbody>
<row> <row>
<entry>&nis; domainname</entry> <entry>NIS domainname</entry>
<entry>An &nis; master server and all of its clients <entry>An NIS master server and all of its clients
(including its slave servers) have a &nis; (including its slave servers) have a NIS
domainname. Similar to an &windowsnt; domain name, the &nis; domainname. Similar to an &windowsnt; domain name, the NIS
domainname does not have anything to do with <acronym>DNS</acronym>.</entry> domainname does not have anything to do with <acronym>DNS</acronym>.</entry>
</row> </row>
<row> <row>
<entry><application>portmap</application></entry> <entry><application>portmap</application></entry>
<entry>Must be running in order to enable <acronym>RPC</acronym> (Remote <entry>Must be running in order to enable <acronym>RPC</acronym> (Remote
Procedure Call, a network protocol used by &nis;). If Procedure Call, a network protocol used by NIS). If
<application>portmap</application> is not running, it will be <application>portmap</application> is not running, it will be
impossible to run an &nis; server, or to act as an NIS impossible to run an NIS server, or to act as an NIS
client.</entry> client.</entry>
</row> </row>
<row> <row>
<entry><application>ypbind</application></entry> <entry><application>ypbind</application></entry>
<entry><quote>Binds</quote> an &nis; client to its &nis; <entry><quote>Binds</quote> an NIS client to its NIS
server. It will take the &nis; domainname from the server. It will take the NIS domainname from the
system, and using <acronym>RPC</acronym>, connect to the system, and using <acronym>RPC</acronym>, connect to the
server. <application>ypbind</application> is the core of server. <application>ypbind</application> is the core of
client-server communication in an &nis; environment; if client-server communication in an NIS environment; if
<application>ypbind</application> dies on a client machine, it <application>ypbind</application> dies on a client machine, it
will not be able to access the &nis; server.</entry> will not be able to access the NIS server.</entry>
</row> </row>
<row> <row>
<entry><application>ypserv</application></entry> <entry><application>ypserv</application></entry>
<entry>Should only be running on &nis; servers; this is the &nis; <entry>Should only be running on NIS servers; this is the NIS
server process itself. If &man.ypserv.8; dies, then the server process itself. If &man.ypserv.8; dies, then the
server will no longer be able to respond to &nis; requests server will no longer be able to respond to NIS requests
(hopefully, there is a slave server to take over for (hopefully, there is a slave server to take over for
it). There are some implementations of &nis; (but not the it). There are some implementations of NIS (but not the
FreeBSD one), that do not try to reconnect to another FreeBSD one), that do not try to reconnect to another
server if the server it used before dies. Often, the server if the server it used before dies. Often, the
only thing that helps in this case is to restart the only thing that helps in this case is to restart the
@ -1183,9 +1186,9 @@ Exports list on foobar:
<row> <row>
<entry><application>rpc.yppasswdd</application></entry> <entry><application>rpc.yppasswdd</application></entry>
<entry>Another process that should only be running on <entry>Another process that should only be running on
&nis; master servers; this is a daemon that will allow &nis; NIS master servers; this is a daemon that will allow NIS
clients to change their &nis; passwords. If this daemon clients to change their NIS passwords. If this daemon
is not running, users will have to login to the &nis; is not running, users will have to login to the NIS
master server and change their passwords there.</entry> master server and change their passwords there.</entry>
</row> </row>
</tbody> </tbody>
@ -1199,7 +1202,7 @@ Exports list on foobar:
<sect2> <sect2>
<title>How Does It Work?</title> <title>How Does It Work?</title>
<para>There are three types of hosts in an &nis; environment: master <para>There are three types of hosts in an NIS environment: master
servers, slave servers, and clients. Servers act as a central servers, slave servers, and clients. Servers act as a central
repository for host configuration information. Master servers repository for host configuration information. Master servers
hold the authoritative copy of this information, while slave hold the authoritative copy of this information, while slave
@ -1208,10 +1211,10 @@ Exports list on foobar:
<para>Information in many files can be shared in this manner. The <para>Information in many files can be shared in this manner. The
<filename>master.passwd</filename>, <filename>group</filename>, <filename>master.passwd</filename>, <filename>group</filename>,
and <filename>hosts</filename> files are commonly shared via &nis;. and <filename>hosts</filename> files are commonly shared via NIS.
Whenever a process on a client needs information that would Whenever a process on a client needs information that would
normally be found in these files locally, it makes a query to the normally be found in these files locally, it makes a query to the
&nis; server that it is bound to instead.</para> NIS server that it is bound to instead.</para>
<sect3> <sect3>
<title>Machine Types</title> <title>Machine Types</title>
@ -1222,30 +1225,30 @@ Exports list on foobar:
<secondary>master server</secondary> <secondary>master server</secondary>
</indexterm> </indexterm>
<listitem> <listitem>
<para>A <emphasis>&nis; master server</emphasis>. <para>A <emphasis>NIS master server</emphasis>.
This server, analogous to a &windowsnt; This server, analogous to a &windowsnt;
primary domain controller, maintains the files used by all primary domain controller, maintains the files used by all
of the &nis; clients. The <filename>passwd</filename>, of the NIS clients. The <filename>passwd</filename>,
<filename>group</filename>, and other various files used by the <filename>group</filename>, and other various files used by the
&nis; clients live on the master server.</para> NIS clients live on the master server.</para>
<note><para>It is possible for one machine to be an &nis; <note><para>It is possible for one machine to be an NIS
master server for more than one &nis; domain. However, this will master server for more than one NIS domain. However, this will
not be covered in this introduction, which assumes a relatively not be covered in this introduction, which assumes a relatively
small-scale &nis; environment.</para></note> small-scale NIS environment.</para></note>
</listitem> </listitem>
<indexterm> <indexterm>
<primary>NIS</primary> <primary>NIS</primary>
<secondary>slave server</secondary> <secondary>slave server</secondary>
</indexterm> </indexterm>
<listitem> <listitem>
<para><emphasis>&nis; slave servers</emphasis>. <para><emphasis>NIS slave servers</emphasis>.
Similar to the &windowsnt; backup domain Similar to the &windowsnt; backup domain
controllers, &nis; slave servers maintain copies of the &nis; controllers, NIS slave servers maintain copies of the NIS
master's data files. &nis; slave servers provide the redundancy, master's data files. NIS slave servers provide the redundancy,
which is needed in important environments. They also help which is needed in important environments. They also help
to balance the load of the master server: &nis; Clients always to balance the load of the master server: NIS Clients always
attach to the &nis; server whose response they get first, and attach to the NIS server whose response they get first, and
this includes slave-server-replies.</para> this includes slave-server-replies.</para>
</listitem> </listitem>
<indexterm> <indexterm>
@ -1253,8 +1256,8 @@ Exports list on foobar:
<secondary>client</secondary> <secondary>client</secondary>
</indexterm> </indexterm>
<listitem> <listitem>
<para><emphasis>&nis; clients</emphasis>. &nis; clients, like most <para><emphasis>NIS clients</emphasis>. NIS clients, like most
&windowsnt; workstations, authenticate against the &nis; server (or the &windowsnt; &windowsnt; workstations, authenticate against the NIS server (or the &windowsnt;
domain controller in the &windowsnt; workstations case) to log on.</para> domain controller in the &windowsnt; workstations case) to log on.</para>
</listitem> </listitem>
</itemizedlist> </itemizedlist>
@ -1262,9 +1265,9 @@ Exports list on foobar:
</sect2> </sect2>
<sect2> <sect2>
<title>Using &nis;/YP</title> <title>Using NIS/YP</title>
<para>This section will deal with setting up a sample &nis; <para>This section will deal with setting up a sample NIS
environment.</para> environment.</para>
<note><para>This section assumes that you are running FreeBSD&nbsp;3.3 <note><para>This section assumes that you are running FreeBSD&nbsp;3.3
@ -1286,7 +1289,7 @@ Exports list on foobar:
currently, when you add a user to the lab, you must run currently, when you add a user to the lab, you must run
<command>adduser</command> on all 15 machines. <command>adduser</command> on all 15 machines.
Clearly, this has to change, so you have decided to convert the Clearly, this has to change, so you have decided to convert the
lab to use &nis;, using two of the machines as servers.</para> lab to use NIS, using two of the machines as servers.</para>
<para>Therefore, the configuration of the lab now looks something <para>Therefore, the configuration of the lab now looks something
like:</para> like:</para>
@ -1304,12 +1307,12 @@ Exports list on foobar:
<row> <row>
<entry><hostid>ellington</hostid></entry> <entry><hostid>ellington</hostid></entry>
<entry><hostid role="ipaddr">10.0.0.2</hostid></entry> <entry><hostid role="ipaddr">10.0.0.2</hostid></entry>
<entry>&nis; master</entry> <entry>NIS master</entry>
</row> </row>
<row> <row>
<entry><hostid>coltrane</hostid></entry> <entry><hostid>coltrane</hostid></entry>
<entry><hostid role="ipaddr">10.0.0.3</hostid></entry> <entry><hostid role="ipaddr">10.0.0.3</hostid></entry>
<entry>&nis; slave</entry> <entry>NIS slave</entry>
</row> </row>
<row> <row>
<entry><hostid>basie</hostid></entry> <entry><hostid>basie</hostid></entry>
@ -1330,13 +1333,13 @@ Exports list on foobar:
</tgroup> </tgroup>
</informaltable> </informaltable>
<para>If you are setting up a &nis; scheme for the first time, it <para>If you are setting up a NIS scheme for the first time, it
is a good idea to think through how you want to go about it. No is a good idea to think through how you want to go about it. No
matter what the size of your network, there are a few decisions matter what the size of your network, there are a few decisions
that need to be made.</para> that need to be made.</para>
<sect4> <sect4>
<title>Choosing a &nis; Domain Name</title> <title>Choosing a NIS Domain Name</title>
<indexterm> <indexterm>
<primary>NIS</primary> <primary>NIS</primary>
@ -1344,83 +1347,83 @@ Exports list on foobar:
</indexterm> </indexterm>
<para>This might not be the <quote>domainname</quote> that you <para>This might not be the <quote>domainname</quote> that you
are used to. It is more accurately called the are used to. It is more accurately called the
<quote>&nis; domainname</quote>. When a client broadcasts its <quote>NIS domainname</quote>. When a client broadcasts its
requests for info, it includes the name of the &nis; domain requests for info, it includes the name of the NIS domain
that it is part of. This is how multiple servers on one that it is part of. This is how multiple servers on one
network can tell which server should answer which request. network can tell which server should answer which request.
Think of the &nis; domainname as the name for a group of hosts Think of the NIS domainname as the name for a group of hosts
that are related in some way.</para> that are related in some way.</para>
<para>Some organizations choose to use their Internet <para>Some organizations choose to use their Internet
domainname for their &nis; domainname. This is not domainname for their NIS domainname. This is not
recommended as it can cause confusion when trying to debug recommended as it can cause confusion when trying to debug
network problems. The &nis; domainname should be unique network problems. The NIS domainname should be unique
within your network and it is helpful if it describes the within your network and it is helpful if it describes the
group of machines it represents. For example, the Art group of machines it represents. For example, the Art
department at Acme Inc. might be in the department at Acme Inc. might be in the
<quote>acme-art</quote> &nis; domain. For this example, <quote>acme-art</quote> NIS domain. For this example,
assume you have chosen the name assume you have chosen the name
<literal>test-domain</literal>.</para> <literal>test-domain</literal>.</para>
<indexterm><primary>SunOS</primary></indexterm> <indexterm><primary>SunOS</primary></indexterm>
<para>However, some operating systems (notably &sunos;) use their <para>However, some operating systems (notably &sunos;) use their
&nis; domain name as their Internet domain name. NIS domain name as their Internet domain name.
If one or more machines on your network have this restriction, If one or more machines on your network have this restriction,
you <emphasis>must</emphasis> use the Internet domain name as you <emphasis>must</emphasis> use the Internet domain name as
your &nis; domain name.</para> your NIS domain name.</para>
</sect4> </sect4>
<sect4> <sect4>
<title>Physical Server Requirements</title> <title>Physical Server Requirements</title>
<para>There are several things to keep in mind when choosing a <para>There are several things to keep in mind when choosing a
machine to use as a &nis; server. One of the unfortunate things machine to use as a NIS server. One of the unfortunate things
about &nis; is the level of dependency the clients have on the about NIS is the level of dependency the clients have on the
server. If a client cannot contact the server for its &nis; server. If a client cannot contact the server for its NIS
domain, very often the machine becomes unusable. The lack of domain, very often the machine becomes unusable. The lack of
user and group information causes most systems to temporarily user and group information causes most systems to temporarily
freeze up. With this in mind you should make sure to choose a freeze up. With this in mind you should make sure to choose a
machine that will not be prone to being rebooted regularly, or machine that will not be prone to being rebooted regularly, or
one that might be used for development. The &nis; server should one that might be used for development. The NIS server should
ideally be a stand alone machine whose sole purpose in life is ideally be a stand alone machine whose sole purpose in life is
to be an &nis; server. If you have a network that is not very to be an NIS server. If you have a network that is not very
heavily used, it is acceptable to put the &nis; server on a heavily used, it is acceptable to put the NIS server on a
machine running other services, just keep in mind that if the machine running other services, just keep in mind that if the
&nis; server becomes unavailable, it will affect NIS server becomes unavailable, it will affect
<emphasis>all</emphasis> of your &nis; clients adversely.</para> <emphasis>all</emphasis> of your NIS clients adversely.</para>
</sect4> </sect4>
</sect3> </sect3>
<sect3> <sect3>
<title>&nis; Servers</title> <title>NIS Servers</title>
<para> The canonical copies of all &nis; information are stored on <para> The canonical copies of all NIS information are stored on
a single machine called the &nis; master server. The databases a single machine called the NIS master server. The databases
used to store the information are called &nis; maps. In FreeBSD, used to store the information are called NIS maps. In FreeBSD,
these maps are stored in these maps are stored in
<filename>/var/yp/[domainname]</filename> where <filename>/var/yp/[domainname]</filename> where
<filename>[domainname]</filename> is the name of the &nis; domain <filename>[domainname]</filename> is the name of the NIS domain
being served. A single &nis; server can support several domains being served. A single NIS server can support several domains
at once, therefore it is possible to have several such at once, therefore it is possible to have several such
directories, one for each supported domain. Each domain will directories, one for each supported domain. Each domain will
have its own independent set of maps.</para> have its own independent set of maps.</para>
<para>&nis; master and slave servers handle all &nis; requests with <para>NIS master and slave servers handle all NIS requests with
the <command>ypserv</command> daemon. <command>ypserv</command> the <command>ypserv</command> daemon. <command>ypserv</command>
is responsible for receiving incoming requests from &nis; clients, is responsible for receiving incoming requests from NIS clients,
translating the requested domain and map name to a path to the translating the requested domain and map name to a path to the
corresponding database file and transmitting data from the corresponding database file and transmitting data from the
database back to the client.</para> database back to the client.</para>
<sect4> <sect4>
<title>Setting Up a &nis; Master Server</title> <title>Setting Up a NIS Master Server</title>
<indexterm> <indexterm>
<primary>NIS</primary> <primary>NIS</primary>
<secondary>server configuration</secondary> <secondary>server configuration</secondary>
</indexterm> </indexterm>
<para>Setting up a master &nis; server can be relatively straight <para>Setting up a master NIS server can be relatively straight
forward, depending on your needs. FreeBSD comes with support forward, depending on your needs. FreeBSD comes with support
for &nis; out-of-the-box. All you need is to add the following for NIS out-of-the-box. All you need is to add the following
lines to <filename>/etc/rc.conf</filename>, and FreeBSD will lines to <filename>/etc/rc.conf</filename>, and FreeBSD will
do the rest for you.</para> do the rest for you.</para>
@ -1433,22 +1436,22 @@ Exports list on foobar:
</step> </step>
<step> <step>
<para><programlisting>nis_server_enable="YES"</programlisting> <para><programlisting>nis_server_enable="YES"</programlisting>
This will tell FreeBSD to start up the &nis; server processes This will tell FreeBSD to start up the NIS server processes
when the networking is next brought up.</para> when the networking is next brought up.</para>
</step> </step>
<step> <step>
<para><programlisting>nis_yppasswdd_enable="YES"</programlisting> <para><programlisting>nis_yppasswdd_enable="YES"</programlisting>
This will enable the <command>rpc.yppasswdd</command> This will enable the <command>rpc.yppasswdd</command>
daemon which, as mentioned above, will allow users to daemon which, as mentioned above, will allow users to
change their &nis; password from a client machine.</para> change their NIS password from a client machine.</para>
</step> </step>
</procedure> </procedure>
<note> <note>
<para>Depending on your &nis; setup, you may need to add <para>Depending on your NIS setup, you may need to add
further entries. See the <link further entries. See the <link
linkend="network-nis-server-is-client">section about &nis; servers linkend="network-nis-server-is-client">section about NIS servers
that are also &nis; clients</link>, below, for that are also NIS clients</link>, below, for
details.</para> details.</para>
</note> </note>
@ -1459,20 +1462,20 @@ Exports list on foobar:
</sect4> </sect4>
<sect4> <sect4>
<title>Initializing the &nis; Maps</title> <title>Initializing the NIS Maps</title>
<indexterm> <indexterm>
<primary>NIS</primary> <primary>NIS</primary>
<secondary>maps</secondary> <secondary>maps</secondary>
</indexterm> </indexterm>
<para>The <emphasis>&nis; maps</emphasis> are database files, <para>The <emphasis>NIS maps</emphasis> are database files,
that are kept in the <filename>/var/yp</filename> directory. that are kept in the <filename>/var/yp</filename> directory.
They are generated from configuration files in the They are generated from configuration files in the
<filename>/etc</filename> directory of the &nis; master, with one <filename>/etc</filename> directory of the NIS master, with one
exception: the <filename>/etc/master.passwd</filename> file. exception: the <filename>/etc/master.passwd</filename> file.
This is for a good reason, you do not want to propagate This is for a good reason, you do not want to propagate
passwords to your <username>root</username> and other passwords to your <username>root</username> and other
administrative accounts to all the servers in the &nis; domain. administrative accounts to all the servers in the NIS domain.
Therefore, before we initialize the &nis; maps, you should:</para> Therefore, before we initialize the NIS maps, you should:</para>
<screen>&prompt.root; <userinput>cp /etc/master.passwd /var/yp/master.passwd</userinput> <screen>&prompt.root; <userinput>cp /etc/master.passwd /var/yp/master.passwd</userinput>
&prompt.root; <userinput>cd /var/yp</userinput> &prompt.root; <userinput>cd /var/yp</userinput>
@ -1482,7 +1485,7 @@ Exports list on foobar:
(<username>bin</username>, <username>tty</username>, (<username>bin</username>, <username>tty</username>,
<username>kmem</username>, <username>games</username>, etc), as <username>kmem</username>, <username>games</username>, etc), as
well as any accounts that you do not want to be propagated to the well as any accounts that you do not want to be propagated to the
&nis; clients (for example <username>root</username> and any other NIS clients (for example <username>root</username> and any other
UID 0 (superuser) accounts).</para> UID 0 (superuser) accounts).</para>
<note><para>Make sure the <note><para>Make sure the
@ -1498,10 +1501,10 @@ Exports list on foobar:
script is available on most &unix; Operating Systems, but not on all. script is available on most &unix; Operating Systems, but not on all.
On Digital UNIX/Compaq Tru64 UNIX it is called On Digital UNIX/Compaq Tru64 UNIX it is called
<command>ypsetup</command>. <command>ypsetup</command>.
Because we are generating maps for an &nis; master, we are Because we are generating maps for an NIS master, we are
going to pass the <option>-m</option> option to going to pass the <option>-m</option> option to
<command>ypinit</command>. <command>ypinit</command>.
To generate the &nis; maps, assuming you already performed To generate the NIS maps, assuming you already performed
the steps above, run:</para> the steps above, run:</para>
<screen>ellington&prompt.root; <userinput>ypinit -m test-domain</userinput> <screen>ellington&prompt.root; <userinput>ypinit -m test-domain</userinput>
@ -1518,7 +1521,7 @@ done with the list, type a &lt;control D&gt;.
master server : ellington master server : ellington
next host to add: <userinput>coltrane</userinput> next host to add: <userinput>coltrane</userinput>
next host to add: <userinput>^D</userinput> next host to add: <userinput>^D</userinput>
The current list of &nis; servers looks like this: The current list of NIS servers looks like this:
ellington ellington
coltrane coltrane
Is this correct? [y/n: y] <userinput>y</userinput> Is this correct? [y/n: y] <userinput>y</userinput>
@ -1532,7 +1535,7 @@ ellington has been setup as an YP master server without any errors.</screen>
<filename>/var/yp/Makefile</filename> from <filename>/var/yp/Makefile</filename> from
<filename>/var/yp/Makefile.dist</filename>. <filename>/var/yp/Makefile.dist</filename>.
When created, this file assumes that you are operating When created, this file assumes that you are operating
in a single server &nis; environment with only FreeBSD in a single server NIS environment with only FreeBSD
machines. Since <literal>test-domain</literal> has machines. Since <literal>test-domain</literal> has
a slave server as well, you must edit a slave server as well, you must edit
<filename>/var/yp/Makefile</filename>:</para> <filename>/var/yp/Makefile</filename>:</para>
@ -1547,12 +1550,12 @@ ellington has been setup as an YP master server without any errors.</screen>
</sect4> </sect4>
<sect4> <sect4>
<title>Setting up a &nis; Slave Server</title> <title>Setting up a NIS Slave Server</title>
<indexterm> <indexterm>
<primary>NIS</primary> <primary>NIS</primary>
<secondary>slave server</secondary> <secondary>slave server</secondary>
</indexterm> </indexterm>
<para>Setting up an &nis; slave server is even more simple than <para>Setting up an NIS slave server is even more simple than
setting up the master. Log on to the slave server and edit the setting up the master. Log on to the slave server and edit the
file <filename>/etc/rc.conf</filename> as you did before. file <filename>/etc/rc.conf</filename> as you did before.
The only difference is that we now must use the The only difference is that we now must use the
@ -1631,22 +1634,22 @@ Don't forget to update map ypservers on ellington.</screen>
<para>These two lines force the slave to sync its maps with <para>These two lines force the slave to sync its maps with
the maps on the master server. Although these entries are the maps on the master server. Although these entries are
not mandatory, since the master server attempts to ensure not mandatory, since the master server attempts to ensure
any changes to its &nis; maps are communicated to its slaves any changes to its NIS maps are communicated to its slaves
and because password information is vital to systems and because password information is vital to systems
depending on the server, it is a good idea to force the depending on the server, it is a good idea to force the
updates. This is more important on busy networks where map updates. This is more important on busy networks where map
updates might not always complete.</para> updates might not always complete.</para>
<para>Now, run the command <command>/etc/netstart</command> on the <para>Now, run the command <command>/etc/netstart</command> on the
slave server as well, which again starts the &nis; server.</para> slave server as well, which again starts the NIS server.</para>
</sect4> </sect4>
</sect3> </sect3>
<sect3> <sect3>
<title>&nis; Clients</title> <title>NIS Clients</title>
<para> An &nis; client establishes what is called a binding to a <para> An NIS client establishes what is called a binding to a
particular &nis; server using the particular NIS server using the
<command>ypbind</command> daemon. <command>ypbind</command> daemon.
<command>ypbind</command> checks the system's default <command>ypbind</command> checks the system's default
domain (as set by the <command>domainname</command> command), domain (as set by the <command>domainname</command> command),
@ -1659,7 +1662,7 @@ Don't forget to update map ypservers on ellington.</screen>
address. If there are several servers available (a master and address. If there are several servers available (a master and
several slaves, for example), <command>ypbind</command> will several slaves, for example), <command>ypbind</command> will
use the address of the first one to respond. From that point use the address of the first one to respond. From that point
on, the client system will direct all of its &nis; requests to on, the client system will direct all of its NIS requests to
that server. <command>ypbind</command> will that server. <command>ypbind</command> will
occasionally <quote>ping</quote> the server to make sure it is occasionally <quote>ping</quote> the server to make sure it is
still up and running. If it fails to receive a reply to one of still up and running. If it fails to receive a reply to one of
@ -1669,18 +1672,18 @@ Don't forget to update map ypservers on ellington.</screen>
server.</para> server.</para>
<sect4> <sect4>
<title>Setting Up a &nis; Client</title> <title>Setting Up a NIS Client</title>
<indexterm> <indexterm>
<primary>NIS</primary> <primary>NIS</primary>
<secondary>client configuration</secondary> <secondary>client configuration</secondary>
</indexterm> </indexterm>
<para>Setting up a FreeBSD machine to be a &nis; client is fairly <para>Setting up a FreeBSD machine to be a NIS client is fairly
straightforward.</para> straightforward.</para>
<procedure> <procedure>
<step> <step>
<para>Edit the file <filename>/etc/rc.conf</filename> and <para>Edit the file <filename>/etc/rc.conf</filename> and
add the following lines in order to set the &nis; domainname add the following lines in order to set the NIS domainname
and start <command>ypbind</command> upon network and start <command>ypbind</command> upon network
startup:</para> startup:</para>
@ -1699,8 +1702,8 @@ nis_client_enable="YES"</programlisting>
<note> <note>
<para>This line will afford anyone with a valid account in <para>This line will afford anyone with a valid account in
the &nis; server's password maps an account. There are the NIS server's password maps an account. There are
many ways to configure your &nis; client by changing this many ways to configure your NIS client by changing this
line. See the <link linkend="network-netgroups">netgroups line. See the <link linkend="network-netgroups">netgroups
section</link> below for more information. section</link> below for more information.
For more detailed reading see O'Reilly's book on For more detailed reading see O'Reilly's book on
@ -1728,7 +1731,7 @@ nis_client_enable="YES"</programlisting>
</procedure> </procedure>
<para>After completing these steps, you should be able to run <para>After completing these steps, you should be able to run
<command>ypcat passwd</command> and see the &nis; server's <command>ypcat passwd</command> and see the NIS server's
passwd map.</para> passwd map.</para>
</sect4> </sect4>
</sect3> </sect3>
@ -1738,7 +1741,7 @@ nis_client_enable="YES"</programlisting>
<title>&nis Security</title> <title>&nis Security</title>
<para>In general, any remote user can issue an RPC to <para>In general, any remote user can issue an RPC to
&man.ypserv.8; and retrieve the contents of your &nis; maps, &man.ypserv.8; and retrieve the contents of your NIS maps,
provided the remote user knows your domainname. To prevent provided the remote user knows your domainname. To prevent
such unauthorized transactions, &man.ypserv.8; supports a such unauthorized transactions, &man.ypserv.8; supports a
feature called <quote>securenets</quote> which can be used to restrict access feature called <quote>securenets</quote> which can be used to restrict access
@ -1787,7 +1790,7 @@ nis_client_enable="YES"</programlisting>
NIS-related traffic should be blocked at your firewall.</para> NIS-related traffic should be blocked at your firewall.</para>
<para>Servers using <filename>/var/yp/securenets</filename> <para>Servers using <filename>/var/yp/securenets</filename>
may fail to serve legitimate &nis; clients with archaic TCP/IP may fail to serve legitimate NIS clients with archaic TCP/IP
implementations. Some of these implementations set all implementations. Some of these implementations set all
host bits to zero when doing broadcasts and/or fail to host bits to zero when doing broadcasts and/or fail to
observe the subnet mask when calculating the broadcast observe the subnet mask when calculating the broadcast
@ -1798,17 +1801,17 @@ nis_client_enable="YES"</programlisting>
<para>Using <filename>/var/yp/securenets</filename> on a <para>Using <filename>/var/yp/securenets</filename> on a
server with such an archaic implementation of TCP/IP is a server with such an archaic implementation of TCP/IP is a
really bad idea and will lead to loss of &nis; functionality really bad idea and will lead to loss of NIS functionality
for large parts of your network.</para> for large parts of your network.</para>
<indexterm><primary>tcpwrapper</primary></indexterm> <indexterm><primary>tcpwrapper</primary></indexterm>
<para>The use of the <application>tcpwrapper</application> <para>The use of the <application>tcpwrapper</application>
package increases the latency of your &nis; server. The package increases the latency of your NIS server. The
additional delay may be long enough to cause timeouts in additional delay may be long enough to cause timeouts in
client programs, especially in busy networks or with slow client programs, especially in busy networks or with slow
&nis; servers. If one or more of your client systems NIS servers. If one or more of your client systems
suffers from these symptoms, you should convert the client suffers from these symptoms, you should convert the client
systems in question into &nis; slave servers and force them systems in question into NIS slave servers and force them
to bind to themselves.</para> to bind to themselves.</para>
</note> </note>
</sect2> </sect2>
@ -1818,12 +1821,12 @@ nis_client_enable="YES"</programlisting>
<para>In our lab, there is a machine <hostid>basie</hostid> that is <para>In our lab, there is a machine <hostid>basie</hostid> that is
supposed to be a faculty only workstation. We do not want to take this supposed to be a faculty only workstation. We do not want to take this
machine out of the &nis; domain, yet the <filename>passwd</filename> machine out of the NIS domain, yet the <filename>passwd</filename>
file on the master &nis; server contains accounts for both faculty and file on the master NIS server contains accounts for both faculty and
students. What can we do?</para> students. What can we do?</para>
<para>There is a way to bar specific users from logging on to a <para>There is a way to bar specific users from logging on to a
machine, even if they are present in the &nis; database. To do this, machine, even if they are present in the NIS database. To do this,
all you must do is add all you must do is add
<literal>-<replaceable>username</replaceable></literal> to the end of <literal>-<replaceable>username</replaceable></literal> to the end of
the <filename>/etc/master.passwd</filename> file on the client the <filename>/etc/master.passwd</filename> file on the client
@ -1887,7 +1890,7 @@ basie&prompt.root;</screen>
machine separately, thus losing the main benefit of NIS: machine separately, thus losing the main benefit of NIS:
<emphasis>centralized</emphasis> administration.</para> <emphasis>centralized</emphasis> administration.</para>
<para>The &nis; developers' solution for this problem is called <para>The NIS developers' solution for this problem is called
<emphasis>netgroups</emphasis>. Their purpose and semantics <emphasis>netgroups</emphasis>. Their purpose and semantics
can be compared to the normal groups used by &unix; file can be compared to the normal groups used by &unix; file
systems. The main differences are the lack of a numeric ID systems. The main differences are the lack of a numeric ID
@ -1902,9 +1905,9 @@ basie&prompt.root;</screen>
used in the remainder of this section demonstrates this used in the remainder of this section demonstrates this
problem.</para> problem.</para>
<para>Let us assume that your successful introduction of &nis; in <para>Let us assume that your successful introduction of NIS in
your laboratory caught your superiors' interest. Your next your laboratory caught your superiors' interest. Your next
job is to extend your &nis; domain to cover some of the other job is to extend your NIS domain to cover some of the other
machines on campus. The two tables contain the names of the machines on campus. The two tables contain the names of the
new users and new machines as well as brief descriptions of new users and new machines as well as brief descriptions of
them.</para> them.</para>
@ -2002,13 +2005,13 @@ basie&prompt.root;</screen>
netgroups. If a new user is added, you will only have to add netgroups. If a new user is added, you will only have to add
the user to one or more netgroups. Those changes are the user to one or more netgroups. Those changes are
independent of each other: no more <quote>for each combination independent of each other: no more <quote>for each combination
of user and machine do...</quote> If your &nis; setup is planned of user and machine do...</quote> If your NIS setup is planned
carefully, you will only have to modify exactly one central carefully, you will only have to modify exactly one central
configuration file to grant or deny access to machines.</para> configuration file to grant or deny access to machines.</para>
<para>The first step is the initialization of the &nis; map <para>The first step is the initialization of the NIS map
netgroup. FreeBSD's &man.ypinit.8; does not create this map by netgroup. FreeBSD's &man.ypinit.8; does not create this map by
default, but its &nis; implementation will support it once it has default, but its NIS implementation will support it once it has
been created. To create an empty map, simply type</para> been created. To create an empty map, simply type</para>
<screen>ellington&prompt.root; <userinput>vi /var/yp/netgroup</userinput></screen> <screen>ellington&prompt.root; <userinput>vi /var/yp/netgroup</userinput></screen>
@ -2042,8 +2045,8 @@ INTERNS (,able,test-domain) (,baker,test-domain)</programlisting>
</listitem> </listitem>
<listitem> <listitem>
<para>The &nis; domain for the account. You can import <para>The NIS domain for the account. You can import
accounts from other &nis; domains into your netgroup if you accounts from other NIS domains into your netgroup if you
are one of the unlucky fellows with more than one NIS are one of the unlucky fellows with more than one NIS
domain.</para> domain.</para>
</listitem> </listitem>
@ -2056,12 +2059,12 @@ INTERNS (,able,test-domain) (,baker,test-domain)</programlisting>
<indexterm><primary>netgroups</primary></indexterm> <indexterm><primary>netgroups</primary></indexterm>
<para>Netgroup names longer than 8 characters should not be <para>Netgroup names longer than 8 characters should not be
used, especially if you have machines running other used, especially if you have machines running other
operating systems within your &nis; domain. The names are operating systems within your NIS domain. The names are
case sensitive; using capital letters for your netgroup case sensitive; using capital letters for your netgroup
names is an easy way to distinguish between user, machine names is an easy way to distinguish between user, machine
and netgroup names.</para> and netgroup names.</para>
<para>Some &nis; clients (other than FreeBSD) cannot handle <para>Some NIS clients (other than FreeBSD) cannot handle
netgroups with a large number of entries. For example, some netgroups with a large number of entries. For example, some
older versions of &sunos; start to cause trouble if a netgroup older versions of &sunos; start to cause trouble if a netgroup
contains more than 15 <emphasis>entries</emphasis>. You can contains more than 15 <emphasis>entries</emphasis>. You can
@ -2078,17 +2081,17 @@ BIGGROUP BIGGRP1 BIGGRP2 BIGGRP3</programlisting>
users within a single netgroup.</para> users within a single netgroup.</para>
</note> </note>
<para>Activating and distributing your new &nis; map is <para>Activating and distributing your new NIS map is
easy:</para> easy:</para>
<screen>ellington&prompt.root; <userinput>cd /var/yp</userinput> <screen>ellington&prompt.root; <userinput>cd /var/yp</userinput>
ellington&prompt.root; <userinput>make</userinput></screen> ellington&prompt.root; <userinput>make</userinput></screen>
<para>This will generate the three &nis; maps <para>This will generate the three NIS maps
<filename>netgroup</filename>, <filename>netgroup</filename>,
<filename>netgroup.byhost</filename> and <filename>netgroup.byhost</filename> and
<filename>netgroup.byuser</filename>. Use &man.ypcat.1; to <filename>netgroup.byuser</filename>. Use &man.ypcat.1; to
check if your new &nis; maps are available:</para> check if your new NIS maps are available:</para>
<screen>ellington&prompt.user; <userinput>ypcat -k netgroup</userinput> <screen>ellington&prompt.user; <userinput>ypcat -k netgroup</userinput>
ellington&prompt.user; <userinput>ypcat -k netgroup.byhost</userinput> ellington&prompt.user; <userinput>ypcat -k netgroup.byhost</userinput>
@ -2141,7 +2144,7 @@ ellington&prompt.user; <userinput>ypcat -k netgroup.byuser</userinput></screen>
<para>Make sure that the line <para>Make sure that the line
<literal>+:::::::::/sbin/nologin</literal> is placed after <literal>+:::::::::/sbin/nologin</literal> is placed after
<literal>+@IT_EMP:::::::::</literal>. Otherwise, all user <literal>+@IT_EMP:::::::::</literal>. Otherwise, all user
accounts imported from &nis; will have <filename>/sbin/nologin</filename> as their accounts imported from NIS will have <filename>/sbin/nologin</filename> as their
login shell.</para> login shell.</para>
</warning> </warning>
@ -2184,7 +2187,7 @@ ellington&prompt.user; <userinput>ypcat -k netgroup.byuser</userinput></screen>
<literal>USERBOX</literal> for the normal <literal>USERBOX</literal> for the normal
workstations. Each of these netgroups contains the netgroups workstations. Each of these netgroups contains the netgroups
that are allowed to login onto these machines. The new that are allowed to login onto these machines. The new
entries for your &nis; map netgroup should look like this:</para> entries for your NIS map netgroup should look like this:</para>
<programlisting>BIGSRV IT_EMP IT_APP <programlisting>BIGSRV IT_EMP IT_APP
SMALLSRV IT_EMP IT_APP ITINTERN SMALLSRV IT_EMP IT_APP ITINTERN
@ -2213,7 +2216,7 @@ USERBOX IT_EMP ITINTERN USERS</programlisting>
<para>Once you have completed this task for all your machines, <para>Once you have completed this task for all your machines,
you will not have to modify the local versions of you will not have to modify the local versions of
<filename>/etc/master.passwd</filename> ever again. All <filename>/etc/master.passwd</filename> ever again. All
further changes can be handled by modifying the &nis; map. Here further changes can be handled by modifying the NIS map. Here
is an example of a possible netgroup map for this is an example of a possible netgroup map for this
scenario with some additional goodies:</para> scenario with some additional goodies:</para>
@ -2262,7 +2265,7 @@ TWO (,hotel,test-domain)
to use machine-based netgroups. If you are deploying a couple of to use machine-based netgroups. If you are deploying a couple of
dozen or even hundreds of identical machines for student labs, dozen or even hundreds of identical machines for student labs,
you should use role-based netgroups instead of machine-based you should use role-based netgroups instead of machine-based
netgroups to keep the size of the &nis; map within reasonable netgroups to keep the size of the NIS map within reasonable
limits.</para> limits.</para>
</sect2> </sect2>
@ -2270,15 +2273,15 @@ TWO (,hotel,test-domain)
<title>Important Things to Remember</title> <title>Important Things to Remember</title>
<para>There are still a couple of things that you will need to do <para>There are still a couple of things that you will need to do
differently now that you are in an &nis; environment.</para> differently now that you are in an NIS environment.</para>
<itemizedlist> <itemizedlist>
<listitem> <listitem>
<para>Every time you wish to add a user to the lab, you <para>Every time you wish to add a user to the lab, you
must add it to the master &nis; server <emphasis>only</emphasis>, must add it to the master NIS server <emphasis>only</emphasis>,
and <emphasis>you must remember to rebuild the NIS and <emphasis>you must remember to rebuild the NIS
maps</emphasis>. If you forget to do this, the new user will maps</emphasis>. If you forget to do this, the new user will
not be able to login anywhere except on the &nis; master. not be able to login anywhere except on the NIS master.
For example, if we needed to add a new user For example, if we needed to add a new user
<username>jsmith</username> to the lab, we would:</para> <username>jsmith</username> to the lab, we would:</para>
@ -2296,7 +2299,7 @@ TWO (,hotel,test-domain)
should not have access to those accounts.</para> should not have access to those accounts.</para>
</listitem> </listitem>
<listitem> <listitem>
<para><emphasis>Keep the &nis; master and slave <para><emphasis>Keep the NIS master and slave
secure, and minimize their downtime</emphasis>. secure, and minimize their downtime</emphasis>.
If somebody either hacks or simply turns off If somebody either hacks or simply turns off
these machines, they have effectively rendered many people without these machines, they have effectively rendered many people without
@ -2304,36 +2307,36 @@ TWO (,hotel,test-domain)
<para>This is the chief weakness of any centralized administration <para>This is the chief weakness of any centralized administration
system. If you do system. If you do
not protect your &nis; servers, you will have a lot of angry not protect your NIS servers, you will have a lot of angry
users!</para> users!</para>
</listitem> </listitem>
</itemizedlist> </itemizedlist>
</sect2> </sect2>
<sect2> <sect2>
<title>&nis; v1 Compatibility</title> <title>NIS v1 Compatibility</title>
<para> FreeBSD's <application>ypserv</application> has some support <para> FreeBSD's <application>ypserv</application> has some support
for serving &nis; v1 clients. FreeBSD's &nis; implementation only for serving NIS v1 clients. FreeBSD's NIS implementation only
uses the &nis; v2 protocol, however other implementations include uses the NIS v2 protocol, however other implementations include
support for the v1 protocol for backwards compatibility with older support for the v1 protocol for backwards compatibility with older
systems. The <application>ypbind</application> daemons supplied systems. The <application>ypbind</application> daemons supplied
with these systems will try to establish a binding to an &nis; v1 with these systems will try to establish a binding to an NIS v1
server even though they may never actually need it (and they may server even though they may never actually need it (and they may
persist in broadcasting in search of one even after they receive a persist in broadcasting in search of one even after they receive a
response from a v2 server). Note that while support for normal response from a v2 server). Note that while support for normal
client calls is provided, this version of <application>ypserv</application> does not handle client calls is provided, this version of <application>ypserv</application> does not handle
v1 map transfer requests; consequently, it cannot be used as a v1 map transfer requests; consequently, it cannot be used as a
master or slave in conjunction with older &nis; servers that only master or slave in conjunction with older NIS servers that only
support the v1 protocol. Fortunately, there probably are not any support the v1 protocol. Fortunately, there probably are not any
such servers still in use today.</para> such servers still in use today.</para>
</sect2> </sect2>
<sect2 id="network-nis-server-is-client"> <sect2 id="network-nis-server-is-client">
<title>&nis; Servers That Are Also &nis; Clients</title> <title>NIS Servers That Are Also NIS Clients</title>
<para> Care must be taken when running <application>ypserv</application> in a multi-server <para> Care must be taken when running <application>ypserv</application> in a multi-server
domain where the server machines are also &nis; clients. It is domain where the server machines are also NIS clients. It is
generally a good idea to force the servers to bind to themselves generally a good idea to force the servers to bind to themselves
rather than allowing them to broadcast bind requests and possibly rather than allowing them to broadcast bind requests and possibly
become bound to each other. Strange failure modes can result if become bound to each other. Strange failure modes can result if
@ -2346,7 +2349,7 @@ TWO (,hotel,test-domain)
<para>You can force a host to bind to a particular server by running <para>You can force a host to bind to a particular server by running
<command>ypbind</command> with the <option>-S</option> <command>ypbind</command> with the <option>-S</option>
flag. If you do not want to do this manually each time you flag. If you do not want to do this manually each time you
reboot your &nis; server, you can add the following lines to reboot your NIS server, you can add the following lines to
your <filename>/etc/rc.conf</filename>:</para> your <filename>/etc/rc.conf</filename>:</para>
<programlisting>nis_client_enable="YES" # run client stuff as well <programlisting>nis_client_enable="YES" # run client stuff as well
@ -2362,10 +2365,10 @@ nis_client_flags="-S <replaceable>NIS domain</replaceable>,<replaceable>server</
<secondary>password formats</secondary> <secondary>password formats</secondary>
</indexterm> </indexterm>
<para>One of the most common issues that people run into when trying <para>One of the most common issues that people run into when trying
to implement &nis; is password format compatibility. If your NIS to implement NIS is password format compatibility. If your NIS
server is using DES encrypted passwords, it will only support server is using DES encrypted passwords, it will only support
clients that are also using DES. For example, if you have clients that are also using DES. For example, if you have
&solaris; &nis; clients in your network, then you will almost certainly &solaris; NIS clients in your network, then you will almost certainly
need to use DES encrypted passwords.</para> need to use DES encrypted passwords.</para>
<para>To check which format your servers <para>To check which format your servers
@ -2405,9 +2408,9 @@ nis_client_flags="-S <replaceable>NIS domain</replaceable>,<replaceable>server</
<para>Having followed the above steps on each of the &os; based NIS <para>Having followed the above steps on each of the &os; based NIS
servers and clients, you can be sure that they all agree on which servers and clients, you can be sure that they all agree on which
password format is used within your network. password format is used within your network.
If you have trouble authenticating on an &nis; client, this If you have trouble authenticating on an NIS client, this
is a pretty good place to start looking for possible problems. is a pretty good place to start looking for possible problems.
Remember: if you want to deploy an &nis; server for a heterogenous Remember: if you want to deploy an NIS server for a heterogenous
network, you will probably have to use DES on all systems network, you will probably have to use DES on all systems
because it is the lowest common standard.</para> because it is the lowest common standard.</para>
</sect2> </sect2>
@ -4275,8 +4278,9 @@ Log file format -->
<primary>NTP</primary> <primary>NTP</primary>
<secondary>ntpd</secondary> <secondary>ntpd</secondary>
</indexterm> </indexterm>
<para>FreeBSD ships with the &man.ntpd.8; NTP server which can <para>FreeBSD ships with the &man.ntpd.8; <acronym role="Network
be used to query other NTP servers to set the clock on your Time Protocol">NTP</acronym> server which can
be used to query other <acronym role="Network Time Protocol">NTP</acronym> servers to set the clock on your
machine or provide time services to others.</para> machine or provide time services to others.</para>
</sect2> </sect2>
@ -4289,7 +4293,7 @@ Log file format -->
</indexterm> </indexterm>
<para>In order to synchronize your clock, you will need to find <para>In order to synchronize your clock, you will need to find
one or more NTP servers to use. Your network administrator or one or more <acronym role="Network Time Protocol">NTP</acronym> servers to use. Your network administrator or
ISP may have set up an NTP server for this purpose&mdash;check ISP may have set up an NTP server for this purpose&mdash;check
their documentation to see if this is the case. There is an their documentation to see if this is the case. There is an
<ulink <ulink