unx33.htm

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<P>Since most UNIX vendors have decided to switch to CD-ROM as the distribution media of choice, most likely you will have a CD-ROM drive somewhere in the network. At this time you have two choices:

<BR></P>

<UL>

<LI>Unplug the drive from where it is currently and add it to the new system to perform the install. Then you have a local CD-ROM drive and can follow the instructions in the installation notes for using a local CD-ROM drive.

<BR>

<BR></LI>

<LI>Use the networking abilities of UNIX to access the drive remotely from the system on which it currently resides.

<BR>

<BR></LI></UL>

<P>Since the network is so much faster than the CD-ROM drive, either choice will work. You just have to be sure that the drive remains available to you for the entire installation process. If someone else is going to need the CD-ROM drive, you will not be 

able to relinquish it to them until the entire install procedure is complete.

<BR></P>

<HR ALIGN=CENTER>

<NOTE>

<IMG SRC="caution.gif" WIDTH = 37 HEIGHT = 35><B>CAUTION: </B>If the system must boot off the CD-ROM drive, it is not always possible to plug any CD-ROM drive into the system. Many UNIX workstation vendors have placed special roms in their CD-ROM drives to 

modify their behavior to look more like a disk drive during the boot process. When in doubt, it is best to have available a model of that workstation vendor's CD-ROM drive for the installation.

<BR></NOTE>

<HR ALIGN=CENTER>

<H4 ALIGN="CENTER">

<CENTER><A ID="I17" NAME="I17">

<FONT SIZE=3><B>Diskless, Dataless, or Stand-Alone Server System?</B>

<BR></FONT></A></CENTER></H4>

<P>Now is the time to decide whether this system is going to be a diskless client of some server, a dataless system, or a stand-alone system or server. You need to make this decision to make sure that the system ends up in the same domain as its server and 

in the same segment of the network if it's diskless.

<BR></P>

<P>In addition you need to make this decision now so you can decide how to partition the disk.

<BR></P>

<P>In general, price determines whether a system is totally diskless. If you can afford a disk drive, you should purchase one and make the system a dataless system. Reserve your use of diskless clients times when it is impractical to place a disk locally 
with the system because of environmental or power concerns; or where access to the system to upgrade the local disk is going to be difficult or impossible. Then it will be necessary to perform all the administration and upgrades on the server system.

<BR></P>

<P>You should see the release notes of your system for specifics, but use the following disk space requirements as a guideline:

<BR></P>

<P><B>Diskless</B>&#151;Since there is no local disk, all disk space resides on the server. Each diskless client must mount its root, swap, temp and spool partitions from the server. Expect to allocate the following from the server:

<BR></P>

<PRE>

<BR>root: 10&#151;20 MB



<BR>swap: Varies by memory size, but 16&#151;256 MB is the normal range.



<BR>spool: 10&#151;20 MB



<BR>tmp: 10&#151;40 MB</PRE>

<P><B>Dataless</B>&#151;Dataless clients use the local disk for each of the partitions listed above for the diskless client.

<BR></P>

<P><B>Stand-alone</B>&#151;If system is for an application user, the same sizes as those for the dataless clients are appropriate.

<BR></P>

<P>In addition, a /usr partition will be needed with an additional 100 MB to hold the remainder of the operating system. If X window system is also to be stored locally, it can require up to an additional 70 MB, depending on the number of tools and fonts 
that are installed. A minimal X installation requires about 30 MB.

<BR></P>

<P>If the user is a developer, the /usr partition will need to be about 150&#151;200 MB to hold the compilers, libraries, additional tools, and local tools the user will need.

<BR></P>

<P><B>Server</B>&#151;Server systems generally need the entire operating system installed. Here is a guideline for overall sizes:

<BR></P>

<PRE>

<BR>root: 20 MB



<BR>swap: varies by memory size, but 64&#151;512 MB is normal range.



<BR>spool: 20&#151;80 MB



<BR>tmp: 20&#151;80 MB



<BR>usr: 200 MB



<BR>X: 70 MB</PRE>

<P>Per diskless client: 50&#151;200 MB (more if large swap areas are needed for the client)

<BR></P>

<P>In addition, a server may have more than one network interface installed. This is so it can serve multiple segments.

<BR></P>

<HR ALIGN=CENTER>

<NOTE>

<IMG SRC="imp.gif" WIDTH = 68 HEIGHT = 35><B>TIP:</B> Consider making one or two systems on the segment servers. Split the remaining systems between those that must stay up regardless of the server and those that are not as critical. Make the critical ones 

stand-alone and the remainder dataless. The performance improvement gained from placing a small disk (even 200 MB) in a system is worthwhile.

<BR></NOTE>

<HR ALIGN=CENTER>

<H4 ALIGN="CENTER">

<CENTER><A ID="I18" NAME="I18">

<FONT SIZE=3><B>Naming the System</B>

<BR></FONT></A></CENTER></H4>

<P>Each UNIX system is given a set of names:

<BR></P>

<UL>

<LI>Host name&#151;a short name it is known by locally.

<BR>

<BR></LI>

<LI>UUCP name&#151;usually the same as the host name. Used for modem-based communications between UNIX systems.

<BR>

<BR></LI>

<LI>Domain name&#151;a name that identifies which set of systems this system is a part of for electronic mail and routing.

<BR>

<BR></LI>

<LI>NIS domain&#151;a name that identifies which set of systems this system is grouped with for systems administration purposes. The set of systems share common password and other systems administration files. See Chapter 37, &quot;Networking,&quot; for 
further details on the NIS system.

<BR>

<BR></LI></UL>

<P>This chapter deals with the systems host and domain names. Using a UUCP name that is different from the host name is covered in Chapter 43, &quot;UUCP Administration.&quot; The NIS Domain is covered in Chapter 37.

<BR></P>

<H5 ALIGN="CENTER">

<CENTER><A ID="I19" NAME="I19">

<FONT SIZE=3><B>Host Name</B>

<BR></FONT></A></CENTER></H5>

<P>A host name is typed often, so it should be relatively short. While it can be up to 256 characters long in System V Release 4 systems, no one wants to type a name that long all the time. A short word usually is desired. If this name is to be shared as 
the UUCP name as well, it should be no longer than 8 characters.

<BR></P>

<HR ALIGN=CENTER>

<NOTE>

<IMG SRC="imp.gif" WIDTH = 68 HEIGHT = 35><B>TIP:</B> At any organization, people generally come and go, and when they go, the system they were using gets reassigned. Hardware also gets replaced. It's not a good idea to name a system for its current user 
or for its current hardware.

<BR>

<BR>These are some poor name choices:

<UL>

<LI>sun1051&#151;Today it might be a Sun Sparc 10/51. Tomorrow it might be a Dec Alpha or something else. Choose a name that will retain its meaning regardless of the changes in hardware.

<BR></LI>

<LI>jerry&#151;It was Jerry's system, but who has it now? The name should help identify the system for the user and the administrators. You will be referring to the system by this name in many contexts.

<BR></LI>

<LI>mis1&#151;Systems migrate, even from department to department. When this system ends up in engineering, calling it mis anything could be confusing.

<BR></LI></UL>

Instead, consider using some name that allows for a selection of one of a group of names.

<BR>

<BR>These are some popular choices:

<UL>

<LI>The names of the seven dwarves&#151;This gives the systems some personality, and at least allows for seven. You could expand to use the names of other characters in stories besides Snow White when more names are needed.

<BR></LI>

<LI>Street names&#151;Be careful, though. If you name the aisles of your cubical system for streets, don't use the same street names for your systems. Moving them around could get confusing.

<BR></LI></UL>

Don't take this tip too literally. If functional names, such as mis1 or database make sense, use them. It isn't that difficult to retire the old name and change the system's name to a new one in the future.

<BR></NOTE>

<HR ALIGN=CENTER>

<H5 ALIGN="CENTER">

<CENTER><A ID="I20" NAME="I20">

<FONT SIZE=3><B>Domain Name (DNS/Mail)</B>

<BR></FONT></A></CENTER></H5>

<P>If you want to uniquely address every UNIX system by name, and you try to use short names for local convenience, you quickly run into the problem bemoaned often on the Internet: &quot;All the good ones are taken.&quot; One way around this problem is the 

same way people resolve it with their own names. You can give systems first, middle, and last names.

<BR></P>

<P>One of the results of UNIX and the Internet growing up together is the domain name system. This allows every machine to be uniquely addressed by giving its fully qualified domain name, which is comprised of its host name and its domain name, separated 
by dots, as in the following:

<BR></P>

<PRE>hostname.localdomain.masterdomain.topdomain</PRE>

<P>As an example, the mail gateway at my company, Myxa Corporation, uses this fully qualified domain name:

<BR></P>

<PRE>dsinc.hv.myxa.com</PRE>

<P>You read this name from right to left as follows:

<BR></P>

<P><B>com:</B> This is the top-level or root domain in the United States for commercial organizations. Other choices include edu, for educational institutions; gov, for governmental bodies; net, for network providers; org, for charitable organizations; and 

us, used mostly for individuals. Outside of the United States, the International Standards Organization (ISO) country code is the top-level domain.

<BR></P>

<P><B>myxa:</B> This is the chosen domain name for the entire organization. Since the company is connected to the Internet, myxa.com had to be unique before it could be assigned.

<BR></P>

<P><B>hv:</B> The company is split into more than one office. This level splits the domains logically and distributes the responsibility for maintaining the local host names. This third level of the domain name is optional and is used only by larger 
organizations to split the administrative responsibility. See Chapter 37 for more details on maintaining a domain name service.

<BR></P>

<P><B>dsinc:</B> This is the actual host name of this system.

<BR></P>

<P>The system is then referred to as dsinc within the local office, dsinc.hv within the company, and dsinc.hv.myxa.com from outside the company. 

<BR></P>

<P>If this is an installation of a system into an existing network, you should already have an existing domain name to use. Then you have to choose only a host name. If this is the first system to install in a local group of systems, consider choosing a 
local domain name as well.

<BR></P>

<HR ALIGN=CENTER>

<NOTE>

<IMG SRC="imp.gif" WIDTH = 68 HEIGHT = 35><B>TIP: </B>Why use a local domain name? In networked systems, a central administration group is responsible for assigning and maintaining all host names and their corresponding addresses. When the number of 
systems gets large, there is too much burden on this one group. It can cause delays while you wait for the administration group to get around to adding your new information to their master files. If they delegate this responsibility for a set of systems to 

a local group, they only need to add the local domain to their files and then you can add systems and make changes as needed.

<BR>

<BR>See Chapter 37 for more details on administering a local domain.

<BR></NOTE>

<HR ALIGN=CENTER>

<P>Only if this is the first system in the organization will you have to choose the remaining levels of the domain name. They should be the same for all systems within the organization.

<BR></P>

<H4 ALIGN="CENTER">

<CENTER><A ID="I21" NAME="I21">

<FONT SIZE=3><B>Choosing Which Packages to Install Locally</B>

<BR></FONT></A></CENTER></H4>

<P>When you made the choice of being a server, stand-alone system, dataless client, or diskless client, you made the base choice of what portions of the operating system to install. You can fine-tune this choice if you need to conserve disk space. Sun's 
Solaris 2.3 gives you a large choice of packages to install. Some of those packages are specific to hardware you may not have installed. You can choose to omit those packages now, and if you change the configuration later, you can always add them to the 
existing installation.

<BR></P>

<P>Sun is not the only vendor that gives choices of packages. System V Release 4.0, which is provided from many vendors, splits the operating system into the major groups of packages:

<BR></P>

<PRE>

<BR>V4 Runtime System



<BR>V4 Software Development



<BR>V4 Networking System



<BR>V4 X-Windowing System



<BR>V4 Real-Time Extensions</PRE>

<P>You can choose which of these you need to install locally. In addition, each of these is broken down further into individual packages. While every system needs the runtime group of packages, not all individual packages within it are required. The 
Runtime System is further broken down into the following:

<BR></P>

<TABLE BORDER>

<TR>

<TD>

<P>compat</P>

<TD>

<P>BSD compatibility package</P>

<TR>

<TD>

<P>crypt</P>

<TD>

<P>Security administration utilities</P>

<TR>

<TD>

<P>ed</P>

<TD>

<P>Editing package</P>

<TR>

<TD>

<P>face</P>

<TD>

<P>AT&amp;T Framed Access Command Environment</P>

<TR>