Chapter 3. Installation

Nik Clayton
3.1. Which platform should I download? I have a 64 bit capable Intel® CPU, but I only see amd64.
3.2. Which file do I download to get FreeBSD?
3.3. What do I do if the install image does not boot?
3.4. Where are the instructions for installing FreeBSD?
3.5. What are the minimum requirements to run FreeBSD?
3.6. How can I make my own custom release or install disk?
3.7. Can Windows® co-exist with FreeBSD?
3.8. Another operating system destroyed my Boot Manager. How do I get it back?
3.9. I booted from a CD, but the install program says no CD-ROM is found. Where did it go?
3.10. Do I need to install the source?
3.11. Do I need to build a kernel?
3.12. Should I use DES, Blowfish, or MD5 passwords and how do I specify which form my users receive?
3.13. What are the limits for memory?
3.14. What are the limits for FFS file systems?
3.15. Why do I get an error message, readin failed after compiling and booting a new kernel?
3.16. Is there a tool to perform post-installation configuration tasks?

3.1.

Which platform should I download? I have a 64 bit capable Intel® CPU, but I only see amd64.

amd64 is the term FreeBSD uses for 64-bit compatible x86 architectures (also known as "x86-64" or "x64"). Most modern computers should use amd64. Older hardware should use i386. When installing on a non-x86-compatible architecture, select the platform which best matches the hardware.

3.2.

Which file do I download to get FreeBSD?

On the Getting FreeBSD page, select [iso] next to the architecture that matches the hardware.

Any of the following can be used:

filedescription
disc1.isoContains enough to install FreeBSD and a minimal set of packages.
dvd1.isoSimilar to disc1.iso but with additional packages.
memstick.imgA bootable image sufficient for writing to a USB stick.
bootonly.isoA minimal image that requires network access during installation to completely install FreeBSD.

pc98 users require these floppy images: floppies/boot.flp, floppies/kern1.flp, floppies/kern2.flp, and floppies/mfsroot1.flp. These images need to be written onto floppies by tools like dd(1).

Full instructions on this procedure and a little bit more about installation issues in general can be found in the Handbook entry on installing FreeBSD.

3.3.

What do I do if the install image does not boot?

This can be caused by not downloading the image in binary mode when using FTP.

Some FTP clients default their transfer mode to ascii and attempt to change any end-of-line characters received to match the conventions used by the client's system. This will almost invariably corrupt the boot image. Check the SHA-256 checksum of the downloaded boot image: if it is not exactly that on the server, then the download process is suspect.

When using a command line FTP client, type binary at the FTP command prompt after getting connected to the server and before starting the download of the image.

3.4.

Where are the instructions for installing FreeBSD?

Installation instructions for versions since FreeBSD 9.0 can be found at Handbook entry on installing FreeBSD. Older instructions can be found in the legacy entry on installing FreeBSD.

3.5.

What are the minimum requirements to run FreeBSD?

FreeBSD requires a 486 or better PC, 64 MB or more of RAM, and at least 1.1 GB of hard disk space.

3.6.

How can I make my own custom release or install disk?

Customized FreeBSD installation media can be created by building a custom release. Follow the instructions in the Release Engineering article.

3.7.

Can Windows® co-exist with FreeBSD?

If Windows® is installed first, then yes. FreeBSD's boot manager will then manage to boot Windows® and FreeBSD. If Windows® is installed afterwards, it will overwrite the boot manager. If that happens, see the next section.

3.8.

Another operating system destroyed my Boot Manager. How do I get it back?

This depends upon the boot manager. The FreeBSD boot selection menu can be reinstalled using boot0cfg(8). For example, to restore the boot menu onto the disk ada0:

# boot0cfg -B ada0

The non-interactive MBR bootloader can be installed using gpart(8):

# gpart bootcode -b /boot/mbr ada0

For more complex situations, including GPT disks, see gpart(8).

3.9.

I booted from a CD, but the install program says no CD-ROM is found. Where did it go?

The usual cause of this problem is a mis-configured CD-ROM drive. Many PCs now ship with the CD-ROM as the slave device on the secondary IDE controller, with no master device on that controller. This is illegal according to the ATAPI specification, but Windows® plays fast and loose with the specification, and the BIOS ignores it when booting. This is why the BIOS was able to see the CD-ROM to boot from it, but why FreeBSD cannot see it to complete the install.

Reconfigure the system so that the CD-ROM is either the master device on the IDE controller it is attached to, or make sure that it is the slave on an IDE controller that also has a master device.

3.10.

Do I need to install the source?

In general, no. There is nothing in the base system which requires the presence of the source to operate. Some ports, like sysutils/lsof, will not build unless the source is installed. In particular, if the port builds a kernel module or directly operates on kernel structures, the source must be installed.

3.11.

Do I need to build a kernel?

Usually not. The supplied GENERIC kernel contains the drivers an ordinary computer will need. freebsd-update(8), the FreeBSD binary upgrade tool, cannot upgrade custom kernels, another reason to stick with the GENERIC kernel when possible. For computers with very limited RAM, such as embedded systems, it may be worthwhile to build a smaller custom kernel containing just the required drivers.

3.12.

Should I use DES, Blowfish, or MD5 passwords and how do I specify which form my users receive?

FreeBSD 7 and 8 use MD5 password hashing by default. Recent versions of FreeBSD use SHA512 by default. These are believed to be more secure than the traditional UNIX® password format, which used a scheme based on the DES algorithm. DES passwords are still available for backwards compatibility with legacy operating systems which still use the less secure password format. FreeBSD also supports the Blowfish and MD5 password formats. Which password format to use for new passwords is controlled by the passwd_format login capability in /etc/login.conf, which takes values of des, blf (if these are available) or md5. See the login.conf(5) manual page for more information about login capabilities.

3.13.

What are the limits for memory?

Memory limits depend on the platform used. On a standard i386™ install, the limit is 4 GB but more memory can be supported through pae(4). See instructions for using 4 GB or more memory on i386.

FreeBSD/pc98 has a limit of 4 GB memory, and PAE can not be used with it. Other architectures supported by FreeBSD have much higher theoretical limits on maximum memory (many terabytes).

3.14.

What are the limits for FFS file systems?

For FFS file systems, the largest file system is practically limited by the amount of memory required to fsck(8) the file system. fsck(8) requires one bit per fragment, which with the default fragment size of 4 KB equates to 32 MB of memory per TB of disk. This does mean that on architectures which limit userland processes to 2 GB (e.g., i386™), the maximum fsck(8)'able filesystem is ~60 TB.

If there was not a fsck(8) memory limit the maximum filesystem size would be 2 ^ 64 (blocks) * 32 KB => 16 Exa * 32 KB => 512 ZettaBytes.

The maximum size of a single FFS file is approximately 2 PB with the default block size of 32 KB. Each 32 KB block can point to 4096 blocks. With triple indirect blocks, the calculation is 32 KB * 12 + 32 KB * 4096 + 32 KB * 4096^2 + 32 KB * 4096^3. Increasing the block size to 64 KB will increase the max file size by a factor of 16.

3.15.

Why do I get an error message, readin failed after compiling and booting a new kernel?

The world and kernel are out of sync. This is not supported. Be sure to use make buildworld and make buildkernel to update the kernel.

Boot the system by specifying the kernel directly at the second stage, pressing any key when the | shows up before loader is started.

3.16.

Is there a tool to perform post-installation configuration tasks?

Yes, head/ users can set WITH_BSDCONFIG in /etc/src.conf. Users of 10.X and higher may also install sysutils/bsdconfig.

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>.