en/handbook/hb-install-system.xml

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<sections>

<version>2.11</version>
<date>2005-08-17</date>

<section>
<title>Chrooting</title>
<subsection>
<title>Optional: Selecting Mirrors</title>
<body>

<p>
In order to download source code quickly it is recommended to select a fast
mirror. Portage will look in your <path>make.conf</path> file for the
GENTOO_MIRRORS variable and use the mirrors listed therein. You can surf to
our <uri link="/main/en/mirrors.xml">mirror list</uri> and search
for a mirror (or mirrors) close to you (as those are most frequently the 
fastest ones), but we provide a nice tool called <c>mirrorselect</c> which
provides you with a nice interface to select the mirrors you want.
</p>
  
<pre caption="Using mirrorselect for the GENTOO_MIRRORS variable">
# <i>mirrorselect -i -o &gt;&gt; /mnt/gentoo/etc/make.conf</i>
</pre>

<warn>
Do not select any IPv6 mirrors. Our stages currently do not support IPv6.
</warn>

<p>
A second important setting is the SYNC setting in <path>make.conf</path>. This
variable contains the rsync server you want to use when updating your Portage
tree (the collection of ebuilds, scripts containing all the information Portage
needs to download and install software). Although you can manually enter a SYNC
server for yourself, <c>mirrorselect</c> can ease that operation for you:
</p>

<pre caption="Selecting an rsync mirror using mirrorselect">
# <i>mirrorselect -i -r -o &gt;&gt; /mnt/gentoo/etc/make.conf</i>
</pre>

<p>
After running <c>mirrorselect</c> it is adviseable to double-check the settings
in <path>/mnt/gentoo/etc/make.conf</path> !
</p>

</body>
</subsection>
<subsection>
<title>Copy DNS Info</title>
<body>

<p>
One thing still remains to be done before we enter the new environment and that
is copying over the DNS information in <path>/etc/resolv.conf</path>. You need
to do this to ensure that networking still works even after entering the new
environment. <path>/etc/resolv.conf</path> contains the nameservers for your
network.
</p>

<pre caption="Copy over DNS information">
<comment>(The "-L" option is needed to make sure we don't copy a symbolic link)</comment>
# <i>cp -L /etc/resolv.conf /mnt/gentoo/etc/resolv.conf</i>
</pre>

</body>
</subsection>
<subsection>
<title>Mounting the proc Filesystem</title>
<body>

<p>
Mount the <path>/proc</path> filesystem on <path>/mnt/gentoo/proc</path> to
allow the installation to use the kernel-provided information even within the
chrooted environment.
</p>

<pre caption="Mounting /proc">
# <i>mount -t proc none /mnt/gentoo/proc</i>
</pre>

</body>
</subsection>
<subsection>
<title>Entering the new Environment</title>
<body>

<p>
Now that all partitions are initialized and the base environment
installed, it is time to enter our new installation environment by
<e>chrooting</e> into it. This means that we change from the current
installation environment (Installation CD or other installation medium) to your
installation system (namely the initialized partitions).
</p>

<p>
This chrooting is done in three steps. First we will change the root
from <path>/</path> (on the installation medium) to <path>/mnt/gentoo</path> 
(on your partitions) using <c>chroot</c>. Then we will create a new environment
using <c>env-update</c>, which essentially creates environment variables.
Finally, we load those variables into memory using <c>source</c>.
</p>

<pre caption = "Chrooting into the new environment">
# <i>chroot /mnt/gentoo /bin/bash</i>
# <i>env-update</i>
 * Caching service dependencies...
# <i>source /etc/profile</i>
</pre>

<p>
Congratulations! You are now inside your own Gentoo Linux environment.
Of course it is far from finished, which is why the installation still
has some sections left :-)
</p>

</body>
</subsection>
<subsection>
<title>Updating the Portage tree</title>
<body>

<p>
You should now update your Portage tree to the latest version. <c>emerge 
--sync</c> does this for you.
</p>

<pre caption="Updating the Portage tree">
# <i>emerge --sync</i>
<comment>(If you're using a slow terminal like some framebuffers or a serial
console, you can add the --quiet option to speed up this process:)</comment>
# <i>emerge --sync --quiet</i>
</pre>

<p>
If you are behind a firewall that blocks rsync traffic, you can use
<c>emerge-webrsync</c> which will download and install a portage snapshot for
you.
</p>

<p>
If you are warned that a new Portage version is available and that you should
update Portage, you should ignore it. Portage will be updated for you later
on during the installation.
</p>

</body>
</subsection>
<subsection>
<title>Choosing the Right Profile</title>
<body>

<p>
First, a small definition is in place.
</p>

<p>
A profile is a building block for any Gentoo system. Not only does it specify
default values for CHOST, CFLAGS and other important variables, it also locks
the system to a certain range of package versions. This is all maintained by the
Gentoo developers.
</p>

<p>
Previously, such a profile was barely touched by the user. However, x86, hppa
and alpha users can choose between two profiles, one for a 2.4 kernel and one
for a 2.6 kernel. This requirement has been imposed to improve the integration
of the 2.6 kernels. The ppc and ppc64 architectures have several profiles
available as well. We will talk about those later.
</p>

<p>
You can see what profile you are currently using with the following command:
</p>

<pre caption="Verifying system profile">
# <i>ls -FGg /etc/make.profile</i>
lrwxrwxrwx  1 48 Apr  8 18:51 /etc/make.profile -> ../usr/portage/profiles/default-linux/x86/2005.1/
</pre>

<p>
If you are using one of the aforementioned three architectures, the default
profile will provide you with a Linux 2.6-based system. This is the recommended
default, but you have the option of choosing another profile too.
</p>

<p>
Some users may wish to install a system based on the older Linux 2.4 profile.
If you have good reason to do this, then you should first check that an
additional profile exists. On x86, we can do this with the following command:
</p>

<pre caption="Finding out if an additional profile exists">
# <i>ls -d /usr/portage/profiles/default-linux/x86/2005.1/2.4</i>
/usr/portage/profiles/default-linux/x86/2005.1/2.4
</pre>

<p>
The above example shows that the additional 2.4 profile exists (i.e. it didn't
complain about missing file or directory). It is recommended that you stay with
the default, but if you wish to switch, you can do so with as follows:
</p>

<pre caption="Switching to a 2.4 profile">
<comment>(Make sure you use the right architecture, the example below is for x86)</comment>
# <i>ln -snf /usr/portage/profiles/default-linux/x86/2005.1/2.4 /etc/make.profile</i>
<comment>(List the files in the 2.4 profile)</comment>
# <i>ls -FGg /etc/make.profile/</i>
total 12
-rw-r--r--  1 939 Dec 10 14:06 packages
-rw-r--r--  1 347 Dec  3  2004 parent
-rw-r--r--  1 573 Dec  3  2004 virtuals
</pre>

<p>
For ppc, there are a number of new profiles provided with 2005.1.
</p>

<pre caption="PPC Profiles">
<comment>(Generic PPC profile, for all PPC machines)</comment>
# <i>ln -snf /usr/portage/profiles/default-linux/ppc/2005.1/ppc /etc/make.profile</i>
<comment>(G3 profile)</comment>
# <i>ln -snf /usr/portage/profiles/default-linux/ppc/2005.1/ppc/G3 /etc/make.profile</i>
<comment>(G3 Pegasos profile)</comment>
# <i>ln -snf /usr/portage/profiles/default-linux/ppc/2005.1/ppc/G3/Pegasos/ /etc/make.profile</i>
<comment>(G4 (Altivec) profile)</comment>
# <i>ln -snf /usr/portage/profiles/default-linux/ppc/2005.1/ppc/G4 /etc/make.profile</i>
<comment>(G4 Pegasos profile)</comment>
# <i>ln -snf /usr/portage/profiles/default-linux/ppc/2005.1/ppc/G4/Pegasos/ /etc/make.profile</i>
</pre>

<p>
For ppc64, there are a number of new profiles provided with 2005.1.
</p>

<pre caption="PPC64 Profiles">
<comment>(Generic 64bit userland PPC64 profile, for all PPC64 machines)</comment>
# <i>ln -snf /usr/portage/profiles/default-linux/ppc/2005.1/ppc64/64bit-userland /etc/make.profile</i>
<comment>(Generic 32bit userland PPC64 profile, for all PPC64 machines)</comment>
# <i>ln -snf /usr/portage/profiles/default-linux/ppc/2005.1/ppc64/32bit-userland /etc/make.profile</i>
<comment>(Each type of userland has sub profiles as follows, with (userland) replaced with the chosen userland from above)</comment>
<comment>(970 profile for JS20)</comment>
# <i>ln -snf /usr/portage/profiles/default-linux/ppc/2005.1/ppc64/(userland)/970 /etc/make.profile</i>
<comment>(G5 profile)</comment>
# <i>ln -snf /usr/portage/profiles/default-linux/ppc/2005.1/ppc64/(userland)/970/pmac /etc/make.profile</i>
<comment>(POWER3 profile)</comment>
# <i>ln -snf /usr/portage/profiles/default-linux/ppc/2005.1/ppc64/(userland)/power3 /etc/make.profile</i>
<comment>(POWER4 profile)</comment>
# <i>ln -snf /usr/portage/profiles/default-linux/ppc/2005.1/ppc64/(userland)/power4 /etc/make.profile</i>
<comment>(POWER5 profile)</comment>
# <i>ln -snf /usr/portage/profiles/default-linux/ppc/2005.1/ppc64/(userland)/power5 /etc/make.profile</i>
<comment>(The multilib profile is not stable as of this release.)</comment>
</pre>

</body>
</subsection>
<subsection id="configure_USE">
<title>Configuring the USE variable</title>
<body>

<p>
<c>USE</c> is one of the most powerful variables Gentoo provides to its users.
Several programs can be compiled with or without optional support for certain
items. For instance, some programs can be compiled with gtk-support, or with
qt-support. Others can be compiled with or without SSL support. Some programs
can even be compiled with framebuffer support (svgalib) instead of X11 support
(X-server).
</p>

<p>
Most distributions compile their packages with support for as much as possible,
increasing the size of the programs and startup time, not to mention an enormous
amount of dependencies. With Gentoo you can define what options a package 
should be compiled with. This is where <c>USE</c> comes into play.
</p>

<p>
In the <c>USE</c> variable you define keywords which are mapped onto
compile-options. For instance, <e>ssl</e> will compile ssl-support in the
programs that support it. <e>-X</e> will remove X-server support (note the minus
sign in front). <e>gnome gtk -kde -qt</e> will compile your programs with gnome
(and gtk) support, and not with kde (and qt) support, making your system fully
tweaked for GNOME.
</p>

<p>
The default <c>USE</c> settings are placed in the <path>make.defaults</path> 
files of your profile. You will find <path>make.defaults</path> files in the
directory which <path>/etc/make.profile</path> points to and all parent 
directories as well. The default <c>USE</c> setting is the sum of all <c>USE</c>
settings in all <path>make.defaults</path> files. What you place in
<path>/etc/make.conf</path> is calculated against these defaults settings. If
you add something to the <c>USE</c> setting, it is added to the default list. If
you remove something from the <c>USE</c> setting (by placing a minus sign in
front of it) it is removed from the default list (if it was in the default list
at all). <e>Never</e> alter anything inside the <path>/etc/make.profile</path>
directory; it gets overwritten when you update Portage!
</p>

<p>
A full description on <c>USE</c> can be found in the second part of the Gentoo
Handbook, <uri link="?part=2&amp;chap=2">USE flags</uri>. A full description on
the available USE flags can be found on your system in
<path>/usr/portage/profiles/use.desc</path>. 
</p>

<pre caption="Viewing available USE flags">
# <i>less /usr/portage/profiles/use.desc</i>
<comment>(You can scroll using your arrow keys, exit by pressing 'q')</comment>
</pre>

<p>
As an example we show a <c>USE</c> setting for a KDE-based system with DVD, ALSA
and CD Recording support:
</p>

<pre caption="Opening /etc/make.conf">
# <i>nano -w /etc/make.conf</i>
</pre>

<pre caption="USE setting">
USE="-gtk -gnome qt kde dvd alsa cdr"
</pre>

</body>
</subsection>
<subsection>
<title>Optional: GLIBC Locales</title>
<body>

<p>
You will probably only use one or maybe two locales on your system. Up until now
after compiling <c>glibc</c> a full set of all available locales will be
created. As of now you can activate the <c>userlocales</c> USE flag and specify
only the locales you will need in <path>/etc/locales.build</path>. Only do this
if you know what locales to choose. This will not work for the bootstrapping,
but when you recompile glibc afterwards it will.
</p>

<pre caption="Activate the userlocales USE flag especially for glibc">
# <i>mkdir -p /etc/portage</i>
# <i>echo "sys-libs/glibc userlocales" >> /etc/portage/package.use</i>
</pre>

<p>
Now specify the locales you want to be able to use:
</p>

<pre caption="Opening /etc/locales.build">
# <i>nano -w /etc/locales.build</i>
</pre>

<p>
The following locales are an example to get both English (United States) and
German (Germany) with the accompanying character formats (like UTF-8).
</p>

<pre caption="Specify your locales">
en_US/ISO-8859-1
en_US.UTF-8/UTF-8
de_DE/ISO-8859-1
de_DE@euro/ISO-8859-15
</pre>

</body>
</subsection>
</section>
<section>
<title>Differences between Stage1, Stage2 and Stage3</title>
<body>

<p>
Now take a seat and think of your previous steps. We asked you to
select a <e>stage1</e>, <e>stage2</e> or <e>stage3</e> and warned you
that your choice is important for further installation steps. Well, this
is the first place where your choice defines the subsequent steps.
</p>

<ul>
<li>
  If you chose <e>stage1</e>, then you have to follow <e>both</e> steps in
  this chapter (starting with <uri link="#doc_chap3">Progressing from Stage1 
  to Stage2</uri>)
</li>
<li>
  If you chose <e>stage2</e> you only can skip the first step
  and immediately start with the second one (<uri link="#doc_chap4">Progressing
  from Stage2 to Stage3</uri>)
</li>
<li>
  If you chose <e>stage3</e> then you can skip both
  steps and continue with <uri link="?part=1&amp;chap=7">Configuring the 
  Kernel</uri>
</li>
</ul>

</body>
</section>
<section>
<title>Progressing from Stage1 to Stage2</title>
<subsection>
<title>Introduction to Bootstrapping</title>
<body>

<p>
So, you want to compile everything from scratch? Okay then :-)
</p>

<p>
In this step, we will <e>bootstrap</e> your Gentoo system. This takes a
long time, but the result is a system that has been optimized from the
ground up for your specific machine and needs.
</p>

<p>
<e>Bootstrapping</e> means building the GNU C Library, GNU Compiler
Collection and several other key system programs. 
</p>

<p>
Before starting the bootstrap, you might want to download all necessary
sourcecode first. If you do not want to do this, continue 
with <uri link="#bootstrap">Bootstrapping the System</uri>.
</p>

</body>
</subsection>
<subsection>
<title>Optional: Downloading the Sources First</title>
<body>

<p>
If you haven't copied over all source code before, then the bootstrap
script will download all necessary files. If you want to 
download the source code first and later bootstrap the system (for instance 
because you don't want to have your internet connection open during the 
compilation) use the <e>-f</e> option of the bootstrap script, which will 
fetch (hence the letter <e>f</e>) all source code for you.
</p>

<pre caption = "Downloading the necessary sources">
# <i>cd /usr/portage</i>
# <i>scripts/bootstrap.sh -f</i>
</pre>

</body>
</subsection>
<subsection id="bootstrap">
<title>Bootstrapping the System</title>
<body>

<p>
Okay then, take your keyboard and punch in the next commands to start
the bootstrap. Then go amuse yourself with something else because this step 
takes quite some time to finish.
</p>

<pre caption = "Bootstrapping the system">
# <i>cd /usr/portage</i>
# <i>scripts/bootstrap.sh</i>
</pre>

<p>
Now continue with the next step, <uri link="#doc_chap4">Progressing from Stage2
to Stage3</uri>.
</p>

</body>
</subsection>
</section>
<section>
<title>Progressing from Stage2 to Stage3</title>
<subsection>
<title>Introduction</title>
<body>

<p>
If you are reading this section, then you have a bootstrapped system
(either because you bootstrapped it previously, or you are using a
<e>stage2</e>). Then it is now time to build all system packages.
</p>

<p>
<e>All</e> system packages? No, not really. In this step, you will build
the system packages of which there are no alternatives to use.
Some system packages have several alternatives (such as system loggers)
and as Gentoo is all about choices, we don't want to force one upon you.
</p>

</body>
</subsection>
<subsection>
<title>Optional: Viewing what will be done</title>
<body>

<p>
If you want to know what packages will be installed, execute <c>emerge
--pretend --emptytree system</c>. This will list all packages that will be 
built. As this list is pretty big, you should also use a pager like 
<c>less</c> or <c>more</c> to go up and down the list.
</p>

<pre caption = "View what 'emerge system' will do">
# <i>emerge --pretend --emptytree system | less</i>
</pre>

<p>
Note that, if you haven't touched the default CFLAGS/CXXFLAGS setting, using 
<c>emerge --pretend --newuse system</c> is sufficient: it will rebuild the
applications that are affected by a change in USE flags (compared to the USE 
flag we used while building the stage2). If you didn't touch 
the USE flag either, why are you running a stage2 installation then?
</p>

</body>
</subsection>
<subsection>
<title>Optional: Downloading the Sources</title>
<body>

<p>
If you want <c>emerge</c> to download the sources before you continue
(for instance because you don't want the internet connection to be left
open while you are building all packages) you can use the <e>--fetchonly</e>
option of <c>emerge</c> which will fetch all sources for you. 
</p>

<pre caption = "Fetching the sources">
# <i>emerge --fetchonly --emptytree system</i>
</pre>

</body>
</subsection>
<subsection>
<title>Building the System</title>
<body>

<p>
To start building the system, execute <c>emerge --emptytree system</c>. Then 
go do something to keep your mind busy, because this step takes a long time to 
complete.
</p>

<pre caption = "Building the System">
# <i>emerge --emptytree system</i>
</pre>

<p>
Again, if you haven't touched the default CFLAGS and CXXFLAGS setting, using
<c>--newuse</c> is sufficient.
</p>

<p>
You can for now safely ignore any warnings about updated configuration files
(and running <c>etc-update</c>). When your Gentoo system is fully installed and
booted, do read our documentation on <uri
link="?part=3&amp;chap=2#doc_chap3">Configuration File Protection</uri>.
</p>

<p>
When the build process has completed, continue with <uri
link="?part=1&amp;chap=7">Configuring the Kernel</uri>.
</p>

</body>
</subsection>
</section>

</sections>