3.3. Pre-installation Tasks

3.3.1. Inventory the Computer

Before installing FreeBSD it is recommended to inventory the components in the computer. The FreeBSD installation routines will show components such as hard disks, network cards, and CDROM drives with their model number and manufacturer. FreeBSD will also attempt to determine the correct configuration for these devices, including information about IRQ and I/O port usage. Due to the vagaries of computer hardware, this process is not always completely successful, and FreeBSD may need some manual configuration.

If another operating system is already installed, use the facilities provided by that operating systems to view the hardware configuration. If the settings of an expansion card are not obvious, check if they are printed on the card itself. Popular IRQ numbers are 3, 5, and 7, and I/O port addresses are normally written as hexadecimal numbers, such as 0x330.

It is recommended to print or write down this information before installing FreeBSD. It may help to use a table, as seen in this example:

Table 3.1. Sample Device Inventory
Device NameIRQI/O port(s)Notes
First hard diskN/AN/A40 GB, made by Seagate, first IDE master
CDROMN/AN/AFirst IDE slave
Second hard diskN/AN/A20 GB, made by IBM, second IDE master
First IDE controller140x1f0 
Network cardN/AN/AIntel® 10/100
ModemN/AN/A3Com® 56K faxmodem, on COM1

Once the inventory of the components in the computer is complete, check if it matches the hardware requirements of the FreeBSD release to install.

3.3.2. Make a Backup

If the computer contains valuable data, ensure it is backed up, and that the backup has been tested before installing FreeBSD. The FreeBSD installer will prompt before writing any data to disk, but once that process has started, it cannot be undone.

3.3.3. Decide Where to Install FreeBSD

If FreeBSD is to be installed on the entire hard disk, skip this section.

However, if FreeBSD will co-exist with other operating systems, a rough understanding of how data is laid out on the disk is useful. Disk Layouts for FreeBSD/i386

A PC disk can be divided into discrete chunks known as partitions. Since FreeBSD also has partitions, naming can quickly become confusing. Therefore, these disk chunks are referred to as slices in FreeBSD. For example, the FreeBSD version of fdisk(8) refers to slices instead of partitions. By design, the PC only supports four partitions per disk. These partitions are called primary partitions. To work around this limitation and allow more than four partitions, a new partition type was created, the extended partition. A disk may contain only one extended partition. Special partitions, called logical partitions, can be created inside this extended partition.

Each partition has a partition ID, which is a number used to identify the type of data on the partition. FreeBSD partitions have the partition ID of 165.

In general, each operating system will identify partitions in a particular way. For example, Windows®, assigns each primary and logical partition a drive letter, starting with C:.

FreeBSD must be installed into a primary partition. If there are multiple disks, a FreeBSD partition can be created on all, or some, of them. When FreeBSD is installed, at least one partition must be available. This might be a blank partition or it might be an existing partition whose data can be overwritten.

If all the partitions on all the disks are in use, free one of them for FreeBSD using the tools provided by an existing operating system, such as Windows® fdisk.

If there is a spare partition, use that. If it is too small, shrink one or more existing partitions to create more available space.

A minimal installation of FreeBSD takes as little as 100 MB of disk space. However, that is a very minimal install, leaving almost no space for files. A more realistic minimum is 250 MB without a graphical environment, and 350 MB or more for a graphical user interface. If other third-party software will be installed, even more space is needed.

You can use a tool such as GParted to resize your partitions and make space for FreeBSD. GParted is known to work on NTFS and is available on a number of Live CD Linux distributions, such as SystemRescueCD.


Incorrect use of a shrinking tool can delete the data on the disk. Always have a recent, working backup before using this type of tool.

Example 3.1. Using an Existing Partition Unchanged

Consider a computer with a single 4 GB disk that already has a version of Windows® installed, where the disk has been split into two drive letters, C: and D:, each of which is 2 GB in size. There is 1 GB of data on C:, and 0.5 GB of data on D:.

This disk has two partitions, one per drive letter. Copy all existing data from D: to C:, which will free up the second partition, ready for FreeBSD.

Example 3.2. Shrinking an Existing Partition

Consider a computer with a single 4 GB disk that already has a version of Windows® installed. When Windows® was installed, it created one large partition, a C: drive that is 4 GB in size. Currently, 1.5 GB of space is used, and FreeBSD should have 2 GB of space.

In order to install FreeBSD, either:

  1. Backup the Windows® data and then reinstall Windows®, asking for a 2 GB partition at install time.

  2. Use one of the tools described above to shrink your Windows® partition.

3.3.4. Collect the Network Configuration Details

Before installing from an FTP site or an NFS server, make note of the network configuration. The installer will prompt for this information so that it can connect to the network to complete the installation. Connecting to an Ethernet Network or Cable/DSL Modem

If using an Ethernet network or an Internet connection using an Ethernet adapter via cable or DSL, the following information is needed:

  1. IP address

  2. IP address of the default gateway

  3. Hostname

  4. DNS server IP addresses

  5. Subnet Mask

If this information is unknown, ask the system administrator or service provider. Make note if this information is assigned automatically using DHCP. Connecting Using a Modem

If using a dialup modem, FreeBSD can still be installed over the Internet, it will just take a very long time.

You will need to know:

  1. The phone number to dial the Internet Service Provider (ISP)

  2. The COM: port the modem is connected to

  3. The username and password for the ISP account

3.3.5. Check for FreeBSD Errata

Although the FreeBSD Project strives to ensure that each release of FreeBSD is as stable as possible, bugs do occasionally creep into the process. On rare occasions those bugs affect the installation process. As these problems are discovered and fixed, they are noted in the FreeBSD Errata, which is found on the FreeBSD website. Check the errata before installing to make sure that there are no late-breaking problems to be aware of.

Information about all releases, including the errata for each release, can be found on the release information section of the FreeBSD website.

3.3.6. Obtain the FreeBSD Installation Files

The FreeBSD installer can install FreeBSD from files located in any of the following places:

Local Media
  • A CDROM or DVD

  • A USB Memory Stick

  • A MS-DOS® partition on the same computer

  • Floppy disks (FreeBSD/pc98 only)

  • An FTP site through a firewall or using an HTTP proxy

  • An NFS server

  • A dedicated parallel or serial connection

If installing from a purchased FreeBSD CD/DVD, skip ahead to Section 3.3.7, “Prepare the Boot Media”.

To obtain the FreeBSD installation files, skip ahead to Section 3.13, “Preparing Custom Installation Media” which explains how to prepare the installation media. After reading that section, come back here and read on to Section 3.3.7, “Prepare the Boot Media”.

3.3.7. Prepare the Boot Media

The FreeBSD installation process is started by booting the computer into the FreeBSD installer. It is not a program that can be run within another operating system. The computer normally boots using the operating system installed on the hard disk, but it can also be configured to boot from a CDROM or from a USB disk.


If installing from a CD/DVD to a computer whose BIOS supports booting from the CD/DVD, skip this section. The FreeBSD CD/DVD images are bootable and can be used to install FreeBSD without any other special preparation.

To create a bootable memory stick, follow these steps:

  1. Acquire the Memory Stick Image

    Memory stick images for FreeBSD 8.X can be downloaded from the ISO-IMAGES/ directory at ftp://ftp.FreeBSD.org/pub/FreeBSD/releases/arch/ISO-IMAGES/version/FreeBSD-version-RELEASE-arch-memstick.img. Replace arch and version with the architecture and the version number to install. For example, the memory stick images for FreeBSD/i386 8.4-RELEASE are available from ftp://ftp.FreeBSD.org/pub/FreeBSD/releases/i386/ISO-IMAGES/8.4/FreeBSD-8.4-RELEASE-i386-memstick.img.


    A different directory path is used for FreeBSD 9.0-RELEASE and later versions. How to download and install FreeBSD 9.X is covered in Chapter 2, Installing FreeBSD 9.X and Later.

    The memory stick image has a .img extension. The ISO-IMAGES/ directory contains a number of different images and the one to use depends on the version of FreeBSD and the type of media supported by the hardware being installed to.


    Before proceeding, back up the data on the USB stick, as this procedure will erase it.

  2. Write the Image File to the Memory Stick

    Procedure 3.1. Using FreeBSD to Write the Image


    The example below lists /dev/da0 as the target device where the image will be written. Be very careful that you have the correct device as the output target, or you may destroy your existing data.

    • Writing the Image with dd(1)

      The .img file is not a regular file that can just be copied to the memory stick. It is an image of the complete contents of the disk. This means that dd(1) must be used to write the image directly to the disk:

      # dd if=FreeBSD-8.4-RELEASE-i386-memstick.img of=/dev/da0 bs=64k

      If an Operation not permitted error is displayed, make certain that the target device is not in use, mounted, or being automounted by another program. Then try again.

    Procedure 3.2. Using Windows® to Write the Image


    Make sure to use the correct drive letter as the output target, as this command will overwrite and destroy any existing data on the specified device.

    1. Obtaining Image Writer for Windows

      Image Writer for Windows is a free application that can correctly write an image file to a memory stick. Download it from https://launchpad.net/win32-image-writer/ and extract it into a folder.

    2. Writing the Image with Image Writer

      Double-click the Win32DiskImager icon to start the program. Verify that the drive letter shown under Device is the drive with the memory stick. Click the folder icon and select the image to be written to the memory stick. Click Save to accept the image file name. Verify that everything is correct, and that no folders on the memory stick are open in other windows. Finally, click Write to write the image file to the drive.

To create the boot floppy images for a FreeBSD/pc98 installation, follow these steps:

  1. Acquire the Boot Floppy Images

    The FreeBSD/pc98 boot disks can be downloaded from the floppies directory, ftp://ftp.FreeBSD.org/pub/FreeBSD/releases/pc98/version-RELEASE/floppies/. Replace version with the version number to install.

    The floppy images have a .flp extension. floppies/ contains a number of different images. Download boot.flp as well as the number of files associated with the type of installation, such as kern.small* or kern*.


    The FTP program must use binary mode to download these disk images. Some web browsers use text or ASCII mode, which will be apparent if the disks are not bootable.

  2. Prepare the Floppy Disks

    Prepare one floppy disk per downloaded image file. It is imperative that these disks are free from defects. The easiest way to test this is to reformat the disks. Do not trust pre-formatted floppies. The format utility in Windows® will not tell about the presence of bad blocks, it simply marks them as bad and ignores them. It is advised to use brand new floppies.


    If the installer crashes, freezes, or otherwise misbehaves, one of the first things to suspect is the floppies. Write the floppy image files to new disks and try again.

  3. Write the Image Files to the Floppy Disks

    The .flp files are not regular files that can be copied to the disk. They are images of the complete contents of the disk. Specific tools must be used to write the images directly to the disk.

    FreeBSD provides a tool called rawrite for creating the floppies on a computer running Windows®. This tool can be downloaded from ftp://ftp.FreeBSD.org/pub/FreeBSD/releases/pc98/ version-RELEASE/tools/ on the FreeBSD FTP site. Download this tool, insert a floppy, then specify the filename to write to the floppy drive:

    C:\> rawrite boot.flp A:

    Repeat this command for each .flp file, replacing the floppy disk each time, being sure to label the disks with the name of the file. Adjust the command line as necessary, depending on where the .flp files are located.

    When writing the floppies on a UNIX®-like system, such as another FreeBSD system, use dd(1) to write the image files directly to disk. On FreeBSD, run:

    # dd if=boot.flp of=/dev/fd0

    On FreeBSD, /dev/fd0 refers to the first floppy disk. Other UNIX® variants might have different names for the floppy disk device, so check the documentation for the system as necessary.

You are now ready to start installing FreeBSD.

All FreeBSD documents are available for download at http://ftp.FreeBSD.org/pub/FreeBSD/doc/

Questions that are not answered by the documentation may be sent to <freebsd-questions@FreeBSD.org>.

Send questions about this document to <freebsd-doc@FreeBSD.org>.