Minimal Gentoo Installation

Gentoo OS Installation from Minimal Disk

This artlicle will show you how to install Gentoo OS from a minimal installation CD on your computer. Before proceeding, please ensure that you have the following:

• A computer infront of you.
• Available connection to internet – you will need to download certain packages during the installation.
• At least one and a half hours of free time.

Obtaining the Minimal Installation Disk

The first thing you need to do is to download the minimal installation disk available from the Gentoo official website. The filename depends on the version you are going to download. The current version (as of writing this article) can be downloaded from:

After obtaining the installation disk, burn it on a CD and plug it into your computer CDROM drive.

Booting from the CD

Ensure that your BIOS settings allows you to boot from the CD. Usually, you can enter BIOS at boot time by pressing the ‘DEL’ key on you keyboard. From there navigate to your boot manager and set the boot options. Recommended boot configuration order is:

• Floppy (if any)
• CDROM (you should have one in order to follow this guide)
• Hard Disk

After the correct boot order is set, go ahead and reboot to the Gentoo Minimal CD. After a short period, during which various modules and components are initialized you will be provided with a command prompt, which should look like this:

Network Configuration

Since a large part of the OS will be downloaded from Internet we will need your network setup at the beginning. To set it up we will use the ifconfig command:

The above commands brings up the eth0 interface, assigns the 192.168.4.140 private IP address, adds the default gateway as 192.168.4.1 and sets the nameserver to 192.168.4.1. Obviously, you would need to edit those values to match your network configuration. Another, alternative way to setup the network (and the one that is described in the Gentoo handbook) is to use the net-setup command. Doing a net-setup will bring a couple of dialog boxes on your monitor asking for various network options – just answer them and you should be all setup.

Starting the SSHd

Once the network is up and running, we can now run the SSH server. This will allow us to connect remotely from another machine and complete the installation from there. To start the SSH server simply run:

Now, set the root password on the liveCD so that you can connect to it from another PC. Please note that allowing root to connect over ssh is not recommended under normal circumstances. If you can’t trust your local network, use a long and complex password, you should use it only once as it will disappear and you will have to set it once again after your first reboot. To change the password do:

Create Partitions

The next step of the Gentoo install is to create the hdd partitions where it will reside. To do so you will need to use the fdisk utility:

NOTE: Depending on your hardware the device name (i.e /dev/sda) might have a different name. For SATA and SCSI discs the devide name is usually /dev/sda, while for IDE it should be /dev/hda

Using the fdisk you will be asked to enter a command name. What we need to achieve is to:

• Create a boot partition.
• Create a swap partition.
• Create one single partition for the rest of the OS.

You might want a different architecture ofcourse and you are free to implement it, but for the purpose of this tutorial we will use the above schema.

In order to create a new partition, enter ‘n’ when asked for a command. The ‘n’ command will create a brand new partition for you. Select primary and then setup a number for the partition (from 1 to 4). Repeat that for each of the three partitions. At the end it should look like:

Next, we have to actually create the partitions and activate the swap:

Mount the freshly created file systems on /mnt/gentoo. Create directories for the other mount points (like /mnt/gentoo/boot) if you need them and mount them too.

Setting up the Stage

To setup the stage, we will need to download it first from Internet and then unpack it, as shown here:

The stage archive file should be near 100MB and might take a while to download and extract, so please be patient.

Next on the install task list is to fetch the latest portage snapshot. To do so:

The portage archive file should be around 40MB big and shouldn’t take too much time to extract. Once the portage is set all we need to do is to chroot the environment:

This should return something like: “>>> Regenerating /etc/ld.so.cache…” which is a sign of success.
Making the Kernel
Now that we have the portage installed and we have chrooted into the target installation system, we need to build the new kernel. On Gentoo, this is really an easy task – all we need is to fetch the kernel sources from the portage and configure it. To fetch the source files:

After calculating the dependencies, the portage system will attempt to download and extract the gentoo sources package. Once extracted, we can start building the new kernel:

Since this is just a short tutorial on how to install the minimal build of Gentoo, I won’t go further into Kernel configurations. If you would like to learn more about it, please have a look at the Gentoo handbook.

Depending on the options you have selected and your system architecture the actual process of linking the new kernel can get from 5 to …. many minutes, so be patient :-) To finalize the kernel build we need to copy the files into their places:

That’s it for the kernel. Lets move to the next step.

Installing vi

Since this is a brand new system, the only available editor would be nano/pico. I personally am used to use vi and I’m feeling rather uncomfortable when I have to deal with nano. So … the next step would be to install vi (actually vim, which stands for ‘vi improved’):

That would get us VIM installed (and will make us happy).

Configuring the System Files

Although we have installed the Kernel we are far from done yet. The /etc/fstab file is the default one and we need to edit it to suit our system architecture. That is – we need to edit the BOOT, ROOT and SWAP and replace them with our actual partition names:

Again, on your system, it might be /dev/hda rather than /dev/sda. Configuring the default network – we don’t want to do it manually everytime the system boots:

If that would be a server installation, you might want to add the SSH Daemon to the startup. Doing so will enable the SSH on boot time automatically:

Set the root password again

We already set the password once at the beginning of the tutorial, but that password was the one used by the livecd. We need to setup the root password for the newly installed system as well:

Optional step – add syslogd and cron daemons

Install a system logger like syslog-ng and a cron daemon like vixie-cron, and add them to the default run level.

Finalizing the installation and adding the Bootloader

For the purpose of the tutorial we will install the GRUB loader. If you would like to install LILO instead, please have a look at the Gentoo Handbook for details on how to do it. To install the GRUB Loader, we need to get it source files first. We do that the same way as the Kernel source files – using emerge:

Once installed we need to configure and tailor it to our own system:

Now install it:

That’s it. We should have a fully working system now. The last thing left is to actually:

Reboot

Exit the chrooted environment, unmount all file systems and reboot:

That’s it! Your new Gentoo install is completed, although you have probably no use of it as it is at the moment. The next step will be to emerge some software or even a graphical interface (such as Gnome).