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<book>

<bookinfo>
<bookbiblio>
<title>Formatting Media For Use With FreeBSD 2.2-RELEASE</title>
<subtitle>A Tutorial</subtitle>

<authorgroup>
<author>
<firstname>Doug</firstname>
<surname>White</surname>
<affiliation>
<address><email>dwhite@resnet.uoregon.edu</email></address>
</affiliation>
</author>
</authorgroup>

<pubdate>March 1997</pubdate>
<abstract><para>This document describes how to slice, partition, and
format hard disk drives and similar media for use with FreeBSD.  The
examples given have been tested under FreeBSD 2.2-GAMMA and may work
for other releases. </para>
</abstract>
</bookbiblio>
</bookinfo>

<chapter>
<title>Introduction & Definitions</title>

<sect1>
<title>Overview</title>
<para>Successfully adding disks to an existing system is the mark of an
experienced system administrator.  Slicing, partitioning, and adding
disks requires a careful dance of proper command and name syntax.  One
slipped finger and an entire disk could disappear in seconds.  This
document is written in an attempt to simplify this process and avoid
accidents.  Thankfully, enhancements to existing tools (notably
sysinstall) have greatly improved this process in recent releases of
FreeBSD.  </para>

<para>There are two possible modes of disk formatting:
<itemizedlist> 

<listitem><para><firstterm>compatibility mode</firstterm>: Arranging a
disk so that it has a slice table for use with other operating
systems.</para> </listitem>

<listitem><para><firstterm>dangerously dedicated mode</firstterm>:
Formatting a disk with no slice table.  This makes the process of
adding disks easier, however non-FreeBSD operating systems may not
accept the disk. </para> </listitem> 
</itemizedlist> 
</para>

<para>For most cases, dedicated mode is the easiest to set up and use
in existing systems, as a new disk is usually dedicated entirely to
FreeBSD.  However, compatibility mode insures optimum interoperability
with future installations at a cost of increased complexity.</para>

<para>In addition to selecting the mode, two methods of slicing the
disk are available.  One is using the system installation tool
<command>/stand/sysinstall</command>.  2.1.7-RELEASE and later
versions of <command>sysinstall</command> contain code to ease setup
of disks during normal system operation, mainly allowing access to the
Label and Partition editors and a Write feature which will update just
the selected disk and slice without affecting other disks.  The other
method is running the tools manually from a root command line.  For
dangerously dedicated mode, only three or four commands are involved
while <command>sysinstall</command> requires some manipulation.</para>
</sect1>
<sect1>
<title>Definitions</title>

<para>UNIX disk management over the centuries has invented many new
definitions for old words.  The following glossary covers the
definitions used in this document and (hopefully) for FreeBSD in
general.  </para>

<!-- I'm tempted to use GLOSSARY here but will resort to a list for
now. -->

<itemizedlist>
<listitem><para>compatibility mode:  Arranging a disk so that it has a slice
table for use with other operating systems.  Oppose dangerously
dedicated mode.</para></listitem>

<listitem><para>dangerously dedicated mode:  Formatting a disk with no slice
table.  This makes the process of adding disks easier, however
non-FreeBSD operating systems may not accept the disk.  Oppose
compatibility mode.</para></listitem>

<listitem><para>disk:   A circular disc,  covered with magnetic or similarly
manipulable material, spun by a motor under a head.  Data is stored on
the disk by changing the pattern of magnetism on the disc, which can
be later read.  Hard disks, CD-ROMs, Magneto-optical,and Zip/Jaz
removables are examples of disks.</para></listitem>

<listitem><para>slice: A division of a disk.  Up to four slices are permitted on one
disk in the PC standard.  Slices are composed of contiguous sectors.
Slices are recorded in a <quote>slice table</quote> used by the system BIOS to
locate bootable partitions.  The slice table is usually called the
Partition Table in DOS parlance.  Maintained by the fdisk utility.</para></listitem>

<listitem><para>partition: A division of a slice.  Usually used in reference
to divisions of the FreeBSD slice of a disk.  Each filesystem and swap
area on a disk resides in a partition.  Maintained using the disklabel
utility.</para></listitem>
	
<listitem><para>sector:  Smallest subdivision of a disk.  One sector usually
represents 512 bytes of data.</para></listitem>

</itemizedlist>
</sect1>

<sect1>
<title>Warnings & Pitfalls</title>

<para>Building disks is not something to take lightly.  It is quite possible
to destroy the contents of other disks in your system if the proper 
precautions are not taken.</para>

<para>In particular, note the following:
<orderedlist>
<listitem><para><emphasis>Type carefully.</>  One wrong number can wipe out
the wrong disk.  Double check your typing before entering the command.  When 
in doubt consult the kernel boot output for the proper device.</para></listitem>
<listitem><para><emphasis>Never set up a boot disk as dangerously dedicated.</> Some PC BIOSs cannot understand the bootblocks and start your system properly.
Make the first disk in <quote>compatibility mode</quote> just to be safe.  
Subsequent non-booting disks are OK to dangerously dedicate.</para></listitem>
</orderedlist>
</para>
</sect1>

<sect1>
<title>Zip, Jaz, and Other Removables</title>

<para>Removable disks can be formatted in the same way as normal hard
disks.  It is essential to have the disk drive connected to the system
and a disk placed in the drive during startup, so the kernel can
determine the drive's geometry.  Check the <command>dmesg</command>
output and make sure your device and the disk's size is listed.  If
the kernel reports 
<informalexample>
<screen>
Can't get the size
</screen>
</informalexample>
then the disk was not in the drive.  In this case, you will need to restart the
machine before attempting to format disks.
</para>
</sect1>

</chapter>
<chapter>
<title>Formatting Disks in Dedicated Mode</title>

<sect1>
<title>Introduction</title>

<para>This section details how to make disks that are totally dedicated to
FreeBSD.  Remember, dedicated mode disks cannot be booted by the PC
architecture.</para>

</sect1>
<sect1>
<title>Making Dedicated Mode Disks using Sysinstall</title>

<para><command>/stand/sysinstall</command>, the system installation
utility, has been expanded in recent versions to make the process of
dividing disks properly a less tiring affair.  The fdisk and disklabel
editors built into sysinstall are GUI tools that remove much of the
confusion from slicing disks.  For FreeBSD versions 2.1.7 and later,
this is perhaps the simplest way to slice disks.</para>

<orderedlist>
<listitem><para>Start sysinstall as root by typing 
<informalexample>
<screen><userinput>/stand/sysinstall</userinput></screen>
</informalexample> 
from the command prompt.</para></listitem>

<listitem><para>Select <command>Index</command>.</para></listitem>
<listitem><para>Select <command>Partition</command>.</para></listitem>
<listitem><para>Select the disk to edit with arrow keys and
<keycap>SPACE</keycap>.</para>
</listitem>
<listitem><para>If you are using this entire disk for FreeBSD, select
<command>A</command>.</para></listitem> 
<listitem><para>When asked: 
<informalexample>
<screen>
Do you want to do this with a true partition entry so as to remain
cooperative with any future possible operating systems on the
drive(s)?
</screen>
</informalexample>answer <command>No</command>.</para></listitem>
<listitem><para>When asked if you still want to do this, answer
<command>Yes</command>.</para></listitem> 
<listitem><para>Select <command>Write</command>.</para></listitem>
<listitem><para>When warned about Writing on installed systems, answer
<command>Yes</command>.</para></listitem> 
<listitem><para><command>Quit</command>the FDISK Editor and
<keycap>ESCAPE</keycap> back to the Index menu.</para></listitem>
<listitem><para>Select <command>Label</command> from the Index
menu.</para></listitem>  
<listitem><para>Label as desired.  For a single partition, enter
<command>C</command> to Create a partition, accept the
default size, partition type Filesystem, and a mountpoint (which isn't
used).</para></listitem> 
<listitem><para>Enter <command>W</command> when done and confirm to
continue.  The filesystem will be newfs'd for you, unless you select 
otherwise (for news partitions you'll want to do this!).  You'll get
the error: 
<informalexample>
<screen>Error mounting /mnt/dev/wd2s1e on /mnt/blah : No such file or directory </screen>
</informalexample>
Ignore.
</para></listitem>
<listitem><para>Exit out by repeatedly pressing <keycap>ESCAPE</keycap>.</para></listitem>
</orderedlist>

</sect1>
<sect1>
<title>Making Dedicated Mode Disks Using the Command Line</title>


<para>Execute the following commands, replacing wd2 with the disk
name.  Lines beginning with # are comments. </para>
<informalexample>
<screen>
<userinput>  
        dd if=/dev/zero of=/dev/rwd2 count=2
        disklabel /dev/rwd2 | disklabel -B -R -r wd2 /dev/stdin
        # We only want one partition, so using slice 'c' should be fine:
        newfs /dev/rwd2c
</userinput>
</screen>
</informalexample>

<para>	If you need to edit the disklabel to create multiple
partitions (such as swap), use the following: </para>
        
<informalexample>
<screen>
<userinput>
        dd if=/dev/zero of=/dev/rwd2 count=2
        disklabel /dev/r$d > /tmp/label
        # Edit disklabel to add partitions:
        vi /tmp/label
        disklabel -B -R -r wd2 /tmp/label
        # newfs partitions appropriately
</userinput>
</screen>
</informalexample>

<para>Your disk is now ready for use.</para>

</sect1>
</chapter>

<chapter>
<title>Making Compatibility Mode Disks</title>

<sect1>
<title>Introduction</title>
<para>The command line is the easiest way to make dedicated disks, and
the worst way to make compatibility disks.  The command-line fdisk
utility requires higher math skills and an in-depth understanding of
the slice table, which is more than most people want to deal with.
Use sysinstall for compatibility disks, as described below.</para>

</sect1>
<sect1>

<title>Making Compatibility Mode Disks Using Sysinstall</title>

<orderedlist>
<listitem><para>Start sysinstall as root by typing 
<informalexample>
<screen><userinput>/stand/sysinstall</></screen>
</informalexample> 
from the command prompt.</para></listitem>

<listitem><para>Select <command>Index</command>.</para> </listitem>
<listitem><para>Select <command>Partition</command>.</para></listitem>
<listitem><para>Select the disk to edit with arrow keys and
<keycap>SPACE</keycap>.
</para></listitem>
<listitem><para>If you are using this entire disk for FreeBSD, select
<command>A</command>.</para></listitem> 

<listitem><para>When asked: 
<informalexample>
<screen>
Do you want to do this with a true partition entry so as to remain
cooperative with any future possible operating systems on the
drive(s)?
</screen>
</informalexample> answer <command>yes</command>.</para></listitem>
<listitem><para>Select <command>Write</command>.</para></listitem>
<listitem><para>When asked to install the boot manager, select None with
<keycap>SPACE</keycap> then hit <keycap>ENTER</keycap> for OK.</para></listitem>
<listitem><para><command>Quit</command> the FDISK Editor.</para></listitem>
<listitem><para>You'll be asked about the boot manager, select
<command>None</command> 
again. </para></listitem> 
<listitem><para>Select <command>Label</command> from the Index
menu.</para></listitem>  
<listitem><para>Label as desired.  For a single partition, accept the
default size, type filesystem, and a mountpoint (which isn't
used).</para></listitem> 
<listitem><para>The filesystem will be newfs'd for you, unless you select otherwise (for news partitions you'll want to do this!).  You'll get the error:
<informalexample>
<screen>
Error mounting /mnt/dev/wd2s1e on /mnt/blah : No such file or directory </screen> 
</informalexample>
Ignore.
</para></listitem>
<listitem><para>Exit out by repeatedly pressing <keycap>ESCAPE</keycap>.</para></listitem>
</orderedlist>

<para>Your new disk is now ready for use.</para>

</sect1>
</chapter>

<chapter>
<title>Other Disk Operations</title>
<sect1>
<title>Adding Swap Space</title>

<para>As a system grows, it's need for swap space can also grow.
Although adding swap space to existing disks is very difficult, a new
disk can be partitioned with additional swap space.  </para>

<para>To add swap space when adding a disk to a system:
<orderedlist>
<listitem><para>When partitioning the disk, edit the disklabel and
allocate the amount of swap space to add in partition `b' and the
remainder in another partition, such as `a' or `e'.  The size is given
in 512 byte blocks.  </para></listitem>
<listitem><para>When newfsing the drive, do NOT newfs the `c'
partition.  Instead, newfs the partition where the non-swap space
lies.</para></listitem> 
<listitem><para>Add an entry to <filename>/etc/fstab</filename> as follows:
<informalexample>
<programlisting>
/dev/wd0b                       none            swap    sw 0 0
</programlisting>
</informalexample>
Change /dev/wd0b to the device of the newly added
space.</para></listitem>
<listitem><para>To make the new space immediately available, use the
<command>swapon</command> command.
<informalexample>
<screen>
<userinput>
$ swapon /dev/sd0b
</userinput>
swapon:  added /dev/sd0b as swap space
</screen>
</informalexample>
</para></listitem>
</orderedlist>
</para>
</sect1>

<sect1>
<title>Copying the Contents of Disks</title>
<!-- Should have specific tag -->
<para>Submitted By:  Renaud Waldura (<email>renaud@softway.com</email>) </para>

<para>To move file from your original base disk to the fresh new one,
do:
<informalexample>
<screen>
<userinput>
mount /dev/wd2 /mnt
pax -r -w -p e /usr/home /mnt
umount /mnt
rm -rf /usr/home/*
mount /dev/wd2 /usr/home
</userinput>
</screen>
</informalexample>
</para>
</sect1>
</chapter>

<chapter>
<title>Credits</title>



<para>The author would like to thank the following individuals for
their contributions to this project:
<itemizedlist>
<listitem><para>Darryl Okahata
(<email>darrylo@hpnmhjw.sr.hp.com</email>) for his
simple dedicated mode setup documentation which I have used repeatedly
on freebsd-questions.</para></listitem>
<listitem><para>Jordan Hubbard
(<email>jkh@freebsd.org</email>) for making
sysinstall useful for this type of task.</para></listitem>
<listitem><para>John Fieber
(<email>jfieber@indiana.edu</email>) for making
information and examples of the DocBook DTD on which this document is
based.</para></listitem>
</itemizedlist>
</para>

</chapter>



</book>
