====== Gentoo Linux Installation ======

Why [[https://www.gwntoo.org|Gentoo Linux]]? In short, because its lightweight, gives you full control on your server and can be much more secure than others bloated Linux distributions. More in detail, see [[selfhost:linux|here]].

These instructions are aimed at supporting you during the installation of your home server, the one on which most, or all, your self-hosted home services will run. This same page can be referred to when installing your //external// server(s), provided they don't already come pre-installed with some other flavour of Linux.

This is not meant to be an exustive guide, as there are plenty of good resources on the topic, specially the amazing [[https://wiki.gentoo.org/wiki/Handbook:AMD64|Gentoo Handbook]] which is the Gentoo Bible for installation.

When installing Gentoo Linux you have the total freedom to choose any single piece of the system, including whether to install or not a Cron Daemon and even a logger daemon. No other distro gives you so much freedom. Moreover, while you can use SystemD and NetworkManager with Gentoo, you are **not** forced to use them, and in fact specially for small servers, they might both be unneeded.

Installing Gentoo Linux is less difficult than you might think. The great [[https://wiki.gentoo.org/wiki/Handbook:AMD64|Gentoo Handbook]] is very well written and also fairly easy to follow if you don't rush it. I assume you are capable of following it up until you can boot a text-only system.


===== The fast&quick Gentoo Installation checklist =====

This is **NOT** a comprehensive installation guide rather a list of quick points to keep in mind while following the already mentioned Gentoo Handbook above.

**Prerequisite**: you already know //where// (on which disk/partition) you are going to install Gentoo and which IP address you want to use for your home (internal) network.

I will assume your home server has one drive dedicated to the Gentoo installation. Data, media, and other files will be stored on a separate RAID array of some kind.

Please do not configure that RAID array now, but read the [[selfhost:storage|Storage Setup]] page.

=== Get Ready for First Boot ===

Burn Gentoo [[https://www.gentoo.org/downloads/|installation ISO]] to a CD or a  [[https://wiki.gentoo.org/wiki/LiveUSB|USB key]], and boot it all the way to the Gentoo command-line prompt.

Setup internet access from your booted installation ISO.

Format your **root** partition on your PC harddrive as EXT4: i recomend EXT4 for the root partition (that's not where you will be storing any data or services!) because it's always supported out of the box and can avoid issues in the future. Let's assume it's /dev/sda2.

Mount your root folder:
<code bash>
mount /dev/sda2 /mnt/gentoo
</code>

Download the [[https://www.gentoo.org/downloads/|Gentoo Stage 3]] tarball for your architecture (arm64, amd64, etc). From the Gentoo boot ISO, you can use **links**, which is a neat text-only web browser.

Decompress the Stage 3, be careful to specify the following options (the 'p' one is critical!):
<code bash>
cd /mnt/gentoo
tar xvfp stage3.blah-blah.tar.zy 
</code>

Prepare and enter the chroot environment:
<code bash>
cp /etc/resolv.conf /mnt/gentoo/etc
modprobe efivarfs
for i in dev dev/pts sys run proc sys/firmware/efi/efivars; do mount /$i /mnt/gentoo/$i -o bind; done
chroot /mnt/gentoo /bin/bash
source /etc/profile
</code>

You are now **inside** your brand new Gentoo Linux installation... But there is still a lot of work to be able to boot it.

You also need, now, to mount the boot/efi partition in side the chroot (let's assume it's **/dev/sda1**), so something like:
<code bash>
mkdir /boot
mount /dev/sda1 /boot
</code>

You need now to setup //portage//, Gentoo package manager.

Accept licenses, put this into <b>/etc/portage/make.conf</b>:
<code>
ACCEPT_LICENSE="-* @FREE @BINARY-REDISTRIBUTABLE @EULA"
</code>

It's time to populate the portage tree:
<code bash>
emerge --sync
</code>

Configure your timezone (choose the correct one):
<code bash>
echo "Europe/Brussels" > /etc/timezone
emerge --config sys-libs/timezone-data
</code>

Configure your locales by editing the file **/etc/locale.gen** and running:
<code bash>
locale-gen
</code>

And select your preferred profile. I would choose a plain basic profile like **default/linux/amd64/17.1** or a **selinux/hardened** one if you feel adventurous:
<code bash>
eselect profile list
</code>

Install and properly setup your CPU flags:
<code bash>
emerge -vp cpuid2cpuflags
echo "*/* $(cpuid2cpuflags)" > /etc/portage/package.use/00cpu-flags
</code>

Now reinstall/recompile the basic system according to your selections:
<code bash>
emerge -uv --deep --newuse @world
</code>

And it's time to install some basic stuff (pick your own! there are also many choices):
<code bash>
 > emerge -vp genkernel gentoo-sources pciutils usbutils mdadm vim tmux cronie  syslog-ng bash-completion chrony dosfstools  io-scheduler-udev-rules intel-microcode 
</code>
Research each one and pick yours.

Now it's time to build the kernel:
<code bash>
eselect kernel set 1
genkernel --mountboot --install all
</code>

Then create a user and set root password:
<code bash>
passwd
useradd user
passwd user
</code>

Setup network and ensure SSH starts by default on boot (i assume your ethernet device is called xxx, you can check in /sys/class/net):
<code bash>
vi /etc/conf/net
rc-update add sshd default
ln -s /et/init.d/net.lo /etc/init.d/net.xxx
rc-update add net.xxx default
</code>

Last, setup boot loader (Grub2 here):
<code bash>
grub-install --target=x86_64-efi --efi-directory=/boot
</code>

and then reboot.


=== Additional settings after first boot ===

Now, you are of course free to install whatever you want, even a fully fledged **Plasma Workspace**, but i strongly advise against. This is a **server** and less stuff you install, the better.

A few more notes and suggestion that will be important in the future.

A few notes to follow:
  * don't bother with setting up the external data disks, you will do it later
  * don't install any graphical user interface, you will not need it
  * don't install SystemD as all commands are not for SystemD (or install it and adapt the commands)

Note: i don't care for SystemD. It does fix a problem i don't have and never had. It's a complication i never had a need for, and Gentoo gives me the choice to not use it. Please use it yourself if you prefer, just adapt the commands where it is involved accordingly.

===== Specific installation finalization =====

(not needed for the **external** server)

You will need to create a special group called **media** which will be used to allow the different tools to access the respective data folders without compromising the security of your installation and media collection:

<code bash>
groupadd media
</code>

this will create a new group called **media**. You will need it later.

There are also a few specific tools we need to install for what comes ahead, let's do it:
<code bash>
emerge -v sys-fs/mdadm
</code>

//mdadm// are the software RAID tools.


Once you have Gentoo installed on your hardware, keep reading.