3. Release Building

FreeBSD releases can be built by anyone with a fast machine and access to a source repository. (That should be everyone, since we offer Subversion access! See the Subversion section in the Handbook for details.) The only special requirement is that the md(4) device must be available. If the device is not loaded into your kernel, then the kernel module should be automatically loaded when mdconfig(8) is executed during the boot media creation phase. All of the tools necessary to build a release are available from the Subversion repository in src/release. These tools aim to provide a consistent way to build FreeBSD releases. A complete release can actually be built with only a single command, including the creation of ISO images suitable for burning to CDROM or DVD, and an FTP install directory. release(7) fully documents the src/release/generate-release.sh script which is used to build a release. generate-release.sh is a wrapper around the Makefile target: make release.

3.1. Building a Release

release(7) documents the exact commands required to build a FreeBSD release. The following sequences of commands can build an 9.2.0 release:

# cd /usr/src/release
# sh generate-release.sh release/9.2.0 /local3/release

After running these commands, all prepared release files are available in /local3/release/R directory.

The release Makefile can be broken down into several distinct steps.

  • Creation of a sanitized system environment in a separate directory hierarchy with make installworld.

  • Checkout from Subversion of a clean version of the system source, documentation, and ports into the release build hierarchy.

  • Population of /etc and /dev in the chrooted environment.

  • chroot into the release build hierarchy, to make it harder for the outside environment to taint this build.

  • make world in the chrooted environment.

  • Build of Kerberos-related binaries.

  • Build GENERIC kernel.

  • Creation of a staging directory tree where the binary distributions will be built and packaged.

  • Build and installation of the documentation toolchain needed to convert the documentation source (SGML) into HTML and text documents that will accompany the release.

  • Build and installation of the actual documentation (user manuals, tutorials, release notes, hardware compatibility lists, and so on.)

  • Package up distribution tarballs of the binaries and sources.

  • Create FTP installation hierarchy.

  • (optionally) Create ISO images for CDROM/DVD media.

For more information about the release build infrastructure, please see release(7).


It is important to remove any site-specific settings from /etc/make.conf. For example, it would be unwise to distribute binaries that were built on a system with CPUTYPE set to a specific processor.

3.2. Contributed Software (ports)

The FreeBSD Ports collection is a collection of over 24,000 third-party software packages available for FreeBSD. The Ports Management Team is responsible for maintaining a consistent ports tree that can be used to create the binary packages that accompany official FreeBSD releases.

3.3. Release ISOs

Starting with FreeBSD 4.4, the FreeBSD Project decided to release all four ISO images that were previously sold on the BSDi/Wind River Systems/FreeBSD Mall official CDROM distributions. Each of the four discs must contain a README.TXT file that explains the contents of the disc, a CDROM.INF file that provides meta-data for the disc so that bsdinstall(8) can validate and use the contents, and a filename.txt file that provides a manifest for the disc. This manifest can be created with a simple command:

/stage/cdrom# find . -type f | sed -e 's/^\.\///' | sort > filename.txt

The specific requirements of each CD are outlined below.

3.3.1. Disc 1

The first disc is almost completely created by make release. The only changes that should be made to the disc1 directory are the addition of a tools directory, and as many popular third party software packages as will fit on the disc. The tools directory contains software that allow users to create installation floppies from other operating systems. This disc should be made bootable so that users of modern PCs do not need to create installation floppy disks.

If a custom kernel of FreeBSD is to be included, then bsdinstall(8) and release(7) must be updated to include installation instructions. The relevant code is contained in src/release and src/usr.sbin/bsdinstall. Specifically, the file src/release/Makefile, and dist.c, dist.h, menus.c, install.c, and Makefile will need to be updated under src/usr.sbin/bsdinstall. Optionally, you may choose to update bsdinstall.8.

3.3.2. Disc 2

The second disc is also largely created by make release. This disc contains a live filesystem that can be used from bsdinstall(8) to troubleshoot a FreeBSD installation. This disc should be bootable and should also contain a compressed copy of the CVS repository in the CVSROOT directory and commercial software demos in the commerce directory.

3.3.3. Multi-volume Support

Sysinstall supports multiple volume package installations. This requires that each disc have an INDEX file containing all of the packages on all volumes of a set, along with an extra field that indicates which volume that particular package is on. Each volume in the set must also have the CD_VOLUME variable set in the cdrom.inf file so that bsdinstall can tell which volume is which. When a user attempts to install a package that is not on the current disc, bsdinstall will prompt the user to insert the appropriate one.

All FreeBSD documents are available for download at https://download.freebsd.org/ftp/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>.