A short guide to Gentoo/FreeBSD

1.  Introduction to FreeBSD

What is FreeBSD?

FreeBSD is a free (license) Unix-like operating system. Back in 1993 when development of 386BSD stopped, two projects were born: NetBSD, commonly known to run on a huge number of architectures, and FreeBSD which supports the x86, amd64, ia64, sparc64 and alpha platforms. FreeBSD is renowned for its stability, performance and security, thus being used from small to huge companies all over the world.

FreeBSD's current production release is version 7.1. Gentoo/FreeBSD is based on version 6.2 and older versions of Gentoo/FreeBSD are discontinued and no longer supported.

What is Gentoo/FreeBSD?

Gentoo/FreeBSD is a subproject of the Gentoo/Alt project, with the goal of providing a fully-capable FreeBSD operating system featuring design sensibilities taken from Gentoo Linux, such as the init system and the Portage package management system.

FreeBSD and Linux

Users migrating from Linux to FreeBSD commonly consider the two operating systems "almost the same". In fact, FreeBSD really shares a lot of similarities with Linux distributions in general. Nevertheless, it has some key differences that are worth noting:

• Contrary to Linux, which actually only refers to the kernel, FreeBSD is a complete operating system, consisting of a C library, userland tools and much more. This development approach makes the overall system very consistent.
• Contrary to the Linux kernel, FreeBSD development is not led by one person, but instead managed by a small group of people called the Core Team.

Besides, FreeBSD also has some technical differences which set it apart from Linux. Some of them are very important to know, even if you don't plan on joining the Gentoo/FreeBSD development effort:

• To get run-time dynamic linking functions like dlopen(), programs do not need to be linked against libdl like on GNU/Linux. Instead they are linked against libc.
• FreeBSD doesn't have an official tool for kernel compilation, thus you'll have to resolve feature dependencies on your own.
• FreeBSD uses UFS/UFS-2 as its filesystems and has no official support for e.g. ReiserFS or XFS. However, there are projects for adding read-only support for these filesystems. Accessing ext2/ext3 partitions is already possible, but you cannot install your system on them.

2.  Installing Gentoo/FreeBSD

Booting the CD

After this short introduction, it's about time to finally install Gentoo/FreeBSD. Unfortunately, we currently lack our own installation media, so you have to choose between two alternative installation methods. The first would be to use an existing FreeBSD installation to partition your hard drive and use it as a base for installing Gentoo/FreeBSD. This guide will describe how to use the FreeSBIE LiveCD as an installation medium for Gentoo/FreeBSD.

First, boot the CD in order to begin the installation process. You'll be presented with a login screen. The username is freesbie, and there is no password. Next, run sudo su to become root, and optionally setup a password. If you want to pass time during the installation process, you can run startx to enter into an Xfce environment, suitable for web browsing, AIM, and other things. Unlike Linux, FreeBSD bases the name of your interface on the driver for the interface. For example, the Intel EtherExpress driver (fxp) appears as fxp0 (driver fxp, first network card). To see what your interface is, use ifconfig:

# ifconfig
fxp0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> mtu 1500
        options=8<VLAN_MTU>
        inet6 fe80::2d0::b7ff:febc:4fe3%fxp0 prefixlen 64 scopeid 0x1
        inet 192.168.0.106 netmask 0xffffff00 broadcast 192.168.0.255
        ether 00:d0:b7:bc:4f:e3
        media: Ethernet autoselect (100baseTX <full-duplex>)
        status: active
lo0: flags=8007<LOOPBACK,MULTICAST> mtu 16384

If the original DHCP request during the CD bootup failed, you can use the dhclient command to obtain an IP:

# dhclient fxp0
DHCPDISCOVER on fxp0 to 255.255.255.255 port 67 interval 9
DHCPOFFER from 192.168.0.1
DHCPREQUEST on fxp0 to 255.255.255.255 port 67
DHCPACK from 192.168.0.1
bound to 192.168.0.106 -- renewal in 302400 seconds

Partitioning the Drive

Now that we have a mount point, it's time to partition the drive. This is done with the sysinstall command:

# sysinstall diskPartitionEditor diskPartitionWrite

We recommend that you use the default layout. Press enter at the dialog, then press a followed by q to accept the default layout. The next screen will present you with the option of a bootloader. For this option, choose "None" as we'll be installing the bootloader later on. Next comes the actual partition sizing and mount points.

This next step also uses sysinstall, but with different arguments:

# sysinstall diskLabelEditor diskLabelCommit

Here, we'll refrain from using the automatic layout, and create one giant root partition, followed by a swap partition. Hit c to create a new partition. A dialog prompts you to enter a size. Go ahead and do so, using MB/GB for setting different sizes, or C for cylinders. For root, choose FS as the partition type, and set the mount point as /mnt/. If you do not adjust the mount point, it will overwrite the FreeSBIE environment! As /boot is not a separate partition, you'll need to disable soft-updates, or your system will not boot! To do so, use the arrow keys to navigate to your newly created partition, then hit the s key, until "Newfs" contains no +S. Now navigate the arrow keys until the "Disk" line is highlighted, and hit c again to create a swap partition. Generally, we recommend a swap space that is twice the size of your RAM. Choose SWAP as the partition type, and don't worry about soft-updates, as it does not apply to swap. Now we're finished, so hit q to finish the process.

When choosing a different mountpoint than / for your partition, sysinstall will actually create a 'd' slice, which the bootloader won't boot from. To fix this, run the following:

# disklabel ad0s1 | sed 's/^  d:/  a:/' | disklabel -R ad0s1 /dev/stdin

This will finalize the partitioning process, and format the drive in UFS for FreeBSD to utilize. This will also mount the drive for you at the mount point specified earlier (/mnt/). You can verify this worked by running mount:

# mount
...
/dev/ad0s1a on /mnt (ufs, local)

Now that you have mounted the target partition, it is time to start on the Gentoo setup.

Gentoo Setup

First, we need to download a stage3 tarball and unpack it into the chroot. Point your browser to http://distfiles.gentoo.org/experimental/x86/freebsd/stages/, grab the latest snapshot, and unpack it into the mountpoint:

# cd /mnt/
(Any other Gentoo mirror which includes the experimental/ directory will also work.)
# wget http://distfiles.gentoo.org/experimental/x86/freebsd/stages/stage3-x86-freebsd-6.2-r1.tar.bz2
# tar -jxvpf stage3-x86-freebsd-6.2-r1.tar.bz2
(You can delete the tarball with the following command if you want to.)
# rm stage3-x86-freebsd-6.2-r1.tar.bz2

In order for your install to work, you need to mount the /dev filesystem from the currently running system into the Gentoo/FreeBSD mount point before proceeding with the chroot.

# mount -t devfs none /mnt/dev/
# cp /etc/resolv.conf /mnt/etc/
# chroot /mnt/ /bin/bash
# env-update && source /etc/profile

After you obtain the Gentoo/FreeBSD overlay, it's time to link /etc/make.profile to the correct profile and get your /etc/make.conf ready for Gentoo/FreeBSD.

Now, you have to obtain a copy of the main Gentoo Portage tree, which depending on your connection might take quite a while.

# emerge --sync
(It's also possible to retrieve the Portage tree in another way:)
# cd /
# wget http://distfiles.gentoo.org/snapshots/portage-latest.tar.bz2
# tar -xjf portage-latest.tar.bz2 -C /usr/
# emerge --metadata

# ln -sf /usr/portage/profiles/default-bsd/fbsd/6.2/x86/ /etc/make.profile
# nano /etc/make.conf
(Please make sure you add at least the following entries:)
CHOST="i686-gentoo-freebsd6.2"
FEATURES="collision-protect"

If you want, you can now rebuild the system's core packages.

# emerge -e system

3.  Setting up for Booting

Set your time zone

First make sure your date and time is set correctly using date yyyymmddHHMM. Use UTC time.

(Check the clock)
# date
Mon Mar  6 00:14:13 UTC 2006

(Set the current date and time if required)
# date 200603060016 (Format is yyyymmddHHMM)
Mon Mar  6 00:16:00 UTC 2006

Next, set your time zone information by using the correct listing in /usr/share/zoneinfo.

# ls /usr/share/zoneinfo
(Using Brussels as an example)
# cp /usr/share/zoneinfo/Europe/Brussels /etc/localtime

# date
Wed Mar  8 00:46:05 CET 2006

Edit /etc/conf.d/clock to define the time zone you used previously.

# nano -w /etc/conf.d/clock
TIMEZONE="Europe/Brussels"

Kernel Installation

If you ran emerge -e system, the sources for the FreeBSD kernel were installed to /usr/src/sys. If you skipped this step, you can get them in the following way:

# emerge freebsd-sources

Configuring and compiling a custom kernel is quite different from compiling Linux, so if you are not familiar with the process we encourage you to have a look at chapter 8 of the FreeBSD handbook. For now, you can do an installation of the GENERIC kernel, which works on most systems. To begin, enter the source directory for the kernel:

# cd /usr/src/sys/

Looking over the layout, you'll see various architectures and subdirectories for various parts of the kernel. To begin the installation, we head into the i386/conf/ directory:

# cd i386/conf/
# ls
.cvsignore      GENERIC         Makefile        PAE
DEFAULTS        GENERIC.hints   NOTES           SMP

The main files to note are GENERIC and GENERIC.hints. As it will be needed by the installation of the kernel, go ahead and copy GENERIC.hints file to /boot/device.hints:

# cp GENERIC.hints /boot/device.hints

This file is used by the kernel drivers for basic configuration information such as IRQ settings. Now it's time to configure the kernel. FreeBSD uses the config command to do this. config uses the given file (in this instance GENERIC) to copy over the required build files to a compile directory in the parent directory. GENERIC is similiar to the .config file for the Linux kernel. Run config to produce the build directory:

# config GENERIC
Kernel build directory is ../compile/GENERIC
Don't forget to ''make cleandepend; make depend''

config has created a GENERIC build directory for us in the parent directory. cd into it, then run the following to do a complete build:

# cd ../compile/GENERIC
# make cleandepend && make depend && make && make install

This will give us a complete kernel to work with. Now we'll need to setup the bootloader for the kernel to boot. The next chapter will discuss two methods of setting up the bootloader: boot0 and grub.

Setting up the bootloader (boot0)

# emerge boot0
(Leave the chroot environment)
# exit
(Issued from outside the chroot)
# fdisk -B -b /mnt/boot/boot0 /dev/adX
# chroot /mnt/ /bin/bash
# disklabel -B adXsY

If you need additional information on setting up boot0, please consult chapter 12 of the FreeBSD handbook. Now it's time to do some basic system configuration and settings.

The next section will look at using the alternative bootloader, grub.

Setting up the bootloader (grub)

As of grub 0.97-r1, UFS slices are readable to grub. This lets us use grub as a bootloader, the prefered method for those coming from a Linux background. To begin, emerge grub and setup the label as bootable. Remember to replace adXsY with the actual number and slice of your disk.

# emerge grub
# disklabel -B adXsY

Now run grub to bring up the command prompt, and set up the partition as shown:

(This is done to prevent disk error 29)
# sysctl kern.geom.debugflags=16
# grub
(Example using ad0s1d)
grub> root (hd0,0,d)
 Filesystem type is ufs2, partition type 0xa5

grub> setup (hd0)
 Checking if "/boot/grub/stage1" exists... yes
 Checking if "/boot/grub/stage2" exists... yes
 Checking if "/boot/grub/ufs2_stage1_5" exists... yes
 Running "embed /boot/grub/ufs2_stage1_5 (hd0)"... 14 sectors are embedded.
succeeded
 Running "install /boot/grub/stage1 (hd0) (hd0)1+14 p (hd0,0,d)/boot/grub/stage
2 /boot/grub/menu.lst"... succeeded
Done.

grub> quit

To make the loader find the kernel on a specific slice (the default is 'a'), add a vfs.root.mountfrom line to the /boot/loader.conf file:

# echo 'vfs.root.mountfrom="ufs:ad0s1d"' >> /boot/loader.conf

When you first boot, you may not receive a grub menu. If so, run this at the prompt:

grub> find /boot/grub/stage1
(The output here is what you'll use in the next command)
 (hd0,0,d)

grub> kernel (hd0,0,d)/boot/loader
  [FreeBSD-a.out, loadaddr=0x200000, text=0x1000, data=0x3a000, bss=0x0, entry=0x200000]

grub> boot

System configuration

First, we are going to setup the filesystem mounting points in /etc/fstab.

# nano /etc/fstab
(This is an example, replace X and Y with the correct numbers for your hard disk.)
#Device         Mountpoint      Fstype          Options         Dump    Pass
/dev/adXsYb     none            swap            sw              0       0
/dev/adXsYa     /               ufs             rw              1       1
/dev/adXsYe     /usr/home       ufs             rw              2       2
/dev/adXsYd     /tmp            ufs             rw              2       2
/dev/acdX       /cdrom          cd9660          ro,noauto       0       0

Now would also be a good time to set up your network connection before the final reboot. You can find all the information necessary to configure your network in the Gentoo Handbook. To have your network interface activated at boot time, you have to add it to the default runlevel:

# rc-update add net.fxp0 default

Your system's hostname can be changed in /etc/conf.d/hostname.

# nano /etc/conf.d/hostname
(Set the HOSTNAME variable to your hostname)
HOSTNAME="tux"

You should also configure your domain name, which is done in the /etc/conf.d/domainname file:

# nano /etc/conf.d/domainname
(Set the dns_domain variable to your domain name, and lo to your local
network interface)
dns_domain_lo="homenetwork"

If you have a NIS domain, you need to define it in the /etc/conf.d/domainname file:

# nano /etc/conf.d/domainname
(Set the nis_domain variable to your NIS domain name, and lo to your local network interface)
nis_domain_lo="my-nisdomain"

In case you need to use another keyboard layout for your language, you have to set the correct value in /etc/conf.d/syscons. The following example uses the Spanish layout, so you'll have to adjust it to your need if you want to use another one.

# nano /etc/conf.d/syscons
KEYMAP="spanish.iso.acc"
(Possible layouts can be found in /usr/share/syscons/keymaps).

Now would be a good time to set a password for the root user and to add another user account for your day-to-day work.

# passwd
# adduser
Username: fred
Full Name: Fred Smith
(Accepting the default here, just hit Enter.)
Uid (Leave empty for default):
(OK to accept the default here as well; hit Enter.)
Login group [fred]:
(Enter your groups here, space separated. They must exist.)
Login group is fred. Invite fred into other groups? []: wheel portage
(OK to accept the default here, hit Enter)
Login class [default]:
(Somewhat of a personal preference.  Make sure the shell exists in /etc/shells)
Shell (sh bash tcsh csh esh ksh zsh sash nologin) [sh] bash
(OK to accept the default here, hit Enter for all these)
User password-based authentication [yes]
Use an empty password (yes/no) [no]:
Use a random password? (yes/no) [no]:
Enter password: password goes here
Enter password again: retype it
(OK to accept the default here, hit Enter)
Lock out the account after creation? [no]:
Username    : fred
Password    : *****
Full Name   : Fred Smith
(This will vary)
Uid         : 1002
Class       :
Groups      : fred wheel portage
Home        : /home/fred
Shell       : /bin/bash
Locked      : no
(Confirm the information is correct)
OK? (yes/no): yes
adduser: INFO: Sucessfully added (fred) to the user database
Add another user? (yes/no): no
Goodbye!
#

Congratulations, you have just finished your Gentoo/FreeBSD installation which you can start exploring after the final reboot. Have fun!

# exit
# reboot

4.  Developing for Gentoo/FreeBSD

How to help

There are many things you could help with, depending on your skill level and spare time:

• Working on current ebuilds: this means working closely with ebuild maintainers in order to create patches or modify ebuilds in a way that can be accepted into the main tree.
• Security: if you are into security, we need you! Although security advisories from the FreeBSD project are tracked and fixed, we can always use help in this area.
• Contacts: we need people who can get in touch with FreeBSD developers to maintain contacts between us and the original project to exchange patches and discuss various problems and their solutions. Note that this should never involve any kind of spamming of mailing lists or IRC channels.
• Testing: the more people are actively using Gentoo/FreeBSD, the more bugs will be discovered, which helps us improving the quality of the port. If you are good at describing bugs or problems, we definitely want to hear from you.
• Other areas where we need help include: system ebuilds, creation of installation CDs, documentation, kernel hacking.

Known issues

At the moment, there are still quite a lot of known issues. Here are the ones really worth noting:

• Some init scripts depend on the clock service which we don't provide right now. You can just remove it from the dependencies of the script and report that on our Bugzilla. Please remember to use the "Gentoo/Alt" product for your submission.

5.  Contact

A list of Gentoo/FreeBSD developers can be found at the project page. Other ways to contact Gentoo/FreeBSD developers include our IRC Channel #gentoo-bsd on Freenode, as well as the gentoo-bsd mailing list.

The contents of this document are licensed under the Creative Commons - Attribution / Share Alike license.