<< Back to man.ChinaUnix.net

[ << ] [ < ] [ Home ] [ > ] [ >> ]

2. Booting the Universal Installation CD


2.a. Hardware Requirements


Before we start, we first list what hardware requirements you need to successfully install Gentoo on your box.

Hardware Requirements

CPU i486 or later
Memory 64 MB
Diskspace 1.5 GB (excluding swap space)
Swap space At least 256 MB

2.b. The Gentoo Universal Installation CD


Gentoo Linux can be installed using one of three stage tarball files. A stage file is a tarball (compressed archive) that contains a minimal environment.

We will opt for a stage3 installation throughout this document. If you want to perform a Gentoo installation using the stage1 or stage2 files, please use the installation instructions in the Gentoo Handbook. They do require a working Internet connection though.

Gentoo Universal Installation CD

An Installation CD is a bootable CDs which contains a self-sustained Gentoo environment. It allows you to boot Linux from the CD. During the boot process your hardware is detected and the appropriate drivers are loaded. The Gentoo Installation CDs are maintained by Gentoo developers.

There currently are two Installation CDs available:

Gentoo also provides a Package CD. This is no Installation CD but an additional resource that you can exploit during the installation of your Gentoo system. It contains prebuilt packages (the so-called GRP set) that allows you to easily and quickly install additional applications (such as OpenOffice.org, KDE, GNOME, ...) immediately after the Gentoo installation and right before you update your Portage tree.

The use of the Package CD is covered later in this document.

2.c. Download, Burn and Boot the Gentoo Universal Installation CD

Downloading and Burning the Installation CD

You can download the Universal Installation CDs (and, if you want to, the Packages CD as well) from one of our mirrors. The Installation CDs are located in the releases/x86/2005.0/installcd directory; the Package CDs are located in the releases/x86/2005.0/packagecd directory.

i686, athlon-xp, pentium3 and pentium4 Package CDs are available via BitTorrent.

Inside those directories you'll find so-called ISO-files. Those are full CD images which you can write on a CD-R.

After downloading the file, you can verify its integrity to see if it is corrupted or not:

To fetch our public key using the GnuPG application, run the following command:

Code listing 1: Obtaining the public key

$ gpg --keyserver pgp.mit.edu --recv-keys 17072058

Now verify the signature:

Code listing 2: Verify the cryptographic signature

$ gpg --verify <signature file> <downloaded iso>

To burn the downloaded ISO(s), you have to select raw-burning. How you do this is highly program-dependent. We will discuss cdrecord and K3B here; more information can be found in our Gentoo FAQ.

Booting the Universal Installation CD

Important: Read this whole subsection before continuing, as you will probably not have the opportunity to read it before doing things later.

Once you have burned your installation CD, it is time to boot it. Remove all CDs from your CD drives, reboot your system and enter the BIOS. This is usually done by hitting DEL, F1 or ESC, depending on your BIOS. Inside the BIOS, change the boot order so that the CD-ROM is tried before the hard disk. This is often found under "CMOS Setup". If you don't do this, your system will just reboot from the hard disk, ignoring the CD-ROM.

Now place the installation CD in the CD-ROM drive (duh) and reboot. You should see a boot prompt. At this screen, you can hit Enter to begin the boot process with the default boot options, or boot the Installation CD with custom boot options by specifying a kernel followed by boot options and then hitting Enter.

Specifying a kernel? Yes, we provide several kernels on our Installation CDs. The default one is gentoo. Other kernels are for specific hardware needs and the -nofb variants which disable framebuffer.

Below you'll find a short overview on the available kernels:

Kernel Description
gentoo Default 2.6 kernel with support for multiple CPUs
gentoo-nofb Same as gentoo but without framebuffer support
memtest86 Test your local RAM for errors

You can also provide kernel options. They represent optional settings you can (de)activate at will. The following list is the same as the one you receive when you press F2 at the bootscreen.

Code listing 3: Options available to pass to your kernel of choice

- agpgart       loads agpgart (use if you have graphic problems,lockups)
- acpi=on       loads support for ACPI firmware
- ide=nodma     force disabling of DMA for malfunctioning IDE devices
- doscsi        scan for scsi devices (breaks some ethernet cards)
- dopcmcia      starts pcmcia service for PCMCIA cdroms
- nofirewire    disables firewire modules in initrd (for firewire cdroms,etc)
- nokeymap      disables keymap selection for non-us keyboard layouts
- docache       cache the entire runtime portion of cd in RAM, allows you
                to umount /mnt/cdrom to mount another cdrom.
- nodetect      causes hwsetup/kudzu and hotplug not to run
- nousb         disables usb module load from initrd, disables hotplug
- nodhcp        dhcp does not automatically start if nic detected
- nohotplug     disables loading hotplug service
- noapic        disable apic (try if having hardware problems nics,scsi,etc)
- noevms2       disable loading of EVMS2 modules
- nolvm2        disable loading of LVM2 modules
- hdx=stroke    allows you to partition the whole harddrive even when your BIOS
                can't handle large harddrives
- noload=module1[,module2[,...]]
                disable loading of specific kernel modules

Now boot your CD, select a kernel (if you are not happy with the default gentoo kernel) and boot options. As an example, we show you how to boot the gentoo kernel, with dopcmcia as kernel parameters:

Code listing 4: Booting an Installation CD

boot: gentoo dopcmcia

You will then be greeted with a boot screen and progress bar. If you are installing Gentoo on a system with a non-US keyboard, make sure you press F2 to switch to verbose mode and follow the prompt. If no selection is made in 10 seconds the default (US keyboard) will be accepted and the boot process will continue. Once the boot process completes, you will be automatically logged in to the "Live" Gentoo Linux as "root", the super user. You should have a root ("#") prompt on the current console and can also switch to other consoles by pressing Alt-F2, Alt-F3 and Alt-F4. Get back to the one you started on by pressing Alt-F1.

Extra Hardware Configuration

When the Installation CD boots, it tries to detect all your hardware devices and loads the appropriate kernel modules to support your hardware. In the vast majority of cases, it does a very good job. However, in some cases, it may not auto-load the kernel modules you need. If the PCI auto-detection missed some of your system's hardware, you will have to load the appropriate kernel modules manually.

In the next example we try to load the 8139too module (support for certain kinds of network interfaces):

Code listing 5: Loading kernel modules

# modprobe 8139too

If you need PCMCIA support, you should start the pcmcia init script:

Code listing 6: Starting the PCMCIA init script

# /etc/init.d/pcmcia start

Optional: Tweaking Hard Disk Performance

If you are an advanced user, you might want to tweak the IDE hard disk performance using hdparm. With the -tT options you can test the performance of your disk (execute it several times to get a more precise impression):

Code listing 7: Testing disk performance

# hdparm -tT /dev/hda

To tweak, you can use any of the following examples (or experiment yourself) which use /dev/hda as disk (substitute with your disk):

Code listing 8: Tweaking hard disk performance

Activate DMA:                       # hdparm -d 1 /dev/hda
Activate Safe Performance Options:  # hdparm -d 1 -A 1 -m 16 -u 1 -a 64 /dev/hda

Optional: User Accounts

If you plan on giving other people access to your installation environment or you want to chat using irssi without root privileges (for security reasons), you need to create the necessary user accounts and change the root password.

To change the root password, use the passwd utility:

Code listing 9: Changing the root password

# passwd
New password: (Enter your new password)
Re-enter password: (Re-enter your password)

To create a user account, we first enter their credentials, followed by its password. We use useradd and passwd for these tasks. In the next example, we create a user called "john".

Code listing 10: Creating a user account

# useradd -m -G users john
# passwd john
New password: (Enter john's password)
Re-enter password: (Re-enter john's password)

You can change your user id from root to the newly created user by using su:

Code listing 11: Changing user id

# su - john

Optional: Viewing Documentation while Installing

If you want to view the Gentoo Handbook (either from-CD or online) during the installation, make sure you have created a user account (see Optional: User Accounts). Then press Alt-F2 to go to a new terminal and log in.

If you want to view the documentation on the CD you can immediately run links2 to read it:

Code listing 12: Viewing the on-CD documentation

# links2 /mnt/cdrom/docs/html/index.html

However, it is preferred that you use the online Gentoo Handbook as it will be more recent than the one provided on the CD. You can view it using links2 as well, but only after having completed the Configuring your Network chapter (otherwise you won't be able to go on the Internet to view the document):

Code listing 13: Viewing the Online Documentation

# links2 http://www.gentoo.org/doc/en/handbook/handbook-x86.xml

You can go back to your original terminal by pressing Alt-F1.

Optional: Starting the SSH Daemon

If you want to allow other users to access your computer during the Gentoo installation (perhaps because those users are going to help you install Gentoo, or even do it for you), you need to create a user account for them and perhaps even provide them with your root password (only do that if you fully trust that user).

To fire up the SSH daemon, execute the following command:

Code listing 14: Starting the SSH daemon

# /etc/init.d/sshd start

To be able to use sshd, you first need to set up your networking. Continue with the chapter on Configuring your Network.

[ << ] [ < ] [ Home ] [ > ] [ >> ]