--- name: "release" section: "7" platform: "freebsd" package: "base" version: "16.0-CURRENT-20261027-61c70dc16a79" release: "FreeBSD 16.0-CURRENT (2026-10-27)" platforms: ["freebsd"] url: "https://new.carta.tech/release/7" --- # release(7) release building infrastructure ## NAME **release** – release building infrastructure ## DESCRIPTION FreeBSD provides a complete build environment suitable for users to make full releases of the FreeBSD operating system. All of the tools necessary to build a release are available from the FreeBSD source code repository in *src/release*. A complete release can be built with only a single command, including the creation of ISO images suitable for burning to CD-ROM, memory stick images, and a network install directory. This command is aptly named “make release”. For some users, it may be desirable to provide an absolutely clean build environment, with no local modifications to the source tree or to [make.conf(5)](/make.conf/5.md), and with clean checkouts of specific versions of the doc, src, and ports trees. For this purpose, a script (*src/release/release.sh*) is provided to automate these checkouts and then execute “make release” in a clean [chroot(8)](/chroot/8.md). Before attempting to build a release, the user is expected to be familiar with the contents of [build(7)](/build/7.md), and should have experience upgrading systems from source. The release build process requires that */usr/obj* be populated with the output of “make buildworld” and “make buildkernel”. This is necessary to provide the object files for the release or, when using *release.sh*, so that the object files for a complete system can be installed into a clean [chroot(8)](/chroot/8.md) environment. If the target release build is for a different architecture or machine type, the *TARGET* and *TARGET\_ARCH* variables must be used. See the supported *release.conf* variables for more information. The release procedure on some architectures may also require that the [md(4)](/md/4.md) (memory disk) device driver be present in the kernel (either by being compiled in or available as a module). This document does not cover source code management, quality assurance, or other aspects of the release engineering process. ## CLEAN RELEASE GENERATION Official releases of FreeBSD are produced in a clean environment to ensure consistency between the versions of the src, ports, and doc trees and to avoid contamination from the host system (such as local patches, changes to [make.conf(5)](/make.conf/5.md), etc.). This is accomplished using the wrapper script *src/release/release.sh*. **release.sh** \[**-c** *release.conf*\] **release.sh** checks out the src/, ports/, and doc/ trees to *CHROOTDIR*, then calls “make buildworld” and “make installworld” to generate a [chroot(8)](/chroot/8.md) environment. Next, “make release” is run within the [chroot(8)](/chroot/8.md) environment and places the result in *$CHROOTDIR/R*. The optional *release.conf* configuration file supports the following variables: - *CHROOTDIR* The directory within which the release will be built. Defaults to */scratch*. - *CHROOT\_MAKEENV* Additional [make(1)](/make/1.md) arguments to pass through, which directly affect the tuning of the build chroot. - *NOGIT* Do not explicitly require the [git(1)](/git/1.md) port to be installed. - *GITROOT* The [git(1)](/git/1.md) host used to check out the various trees. Defaults to *https://git.FreeBSD.org*. - *SRCBRANCH* The src/ branch to use. Defaults to **-b** *main*. - *PORTBRANCH* The ports/ branch to use. Defaults to *head/@rHEAD*. - *TARGET* The target machine type for cross-building a release. - *TARGET\_ARCH* The target machine architecture for cross-building a release. For the supported list of *TARGET* and *TARGET\_ARCH* combinations, consult the output of “make targets” as documented in [build(7)](/build/7.md). - *KERNEL* The target kernel configuration to use. Defaults to *GENERIC*. Multiple *KERNEL* entries may be specified. - *MAKE\_CONF* The [make.conf(5)](/make.conf/5.md) to use for the release build. Defaults to */dev/null* to prevent polluting the release with local system changes. - *SRC\_CONF* The [src.conf(5)](/src.conf/5.md) to use for the release build. Defaults to */dev/null* to prevent polluting the release with local system changes. - *MAKE\_FLAGS* Additional flags to pass to [make(1)](/make/1.md). - *WORLD\_FLAGS* Additional flags to pass to [make(1)](/make/1.md) during the “buildworld” phase. Defaults to setting the number of [make(1)](/make/1.md) jobs (*-j*) to the number of CPUs available on a SMP-capable system. - *KERNEL\_FLAGS* Additional flags to pass to [make(1)](/make/1.md) during the “buildkernel” phase. Defaults to setting the number of [make(1)](/make/1.md) jobs (*-j*) to half the number of CPUs available on a SMP-capable system. - *NOPORTS* Set to a non-empty value to skip the ports/ tree checkout. When set, *NOPORTS* will prevent the *ports.txz* distribution package from being created. - *WITH\_DVD* Set to a non-empty value to include the **dvdrom** target. - *WITH\_COMPRESSED\_IMAGES* Set to a non-empty value to compress the release images with [xz(1)](/xz/1.md). The original (uncompressed) images are not removed. - *XZ\_THREADS* (*int*) Set to the number of threads [xz(1)](/xz/1.md) should use when compressing images. By default, *XZ\_THREADS* is set to *0*, which uses all available cores on the system. - *VCSCMD* The command run to obtain the source trees. Defaults to "**git** **clone** **-q**". - *CHROOTBUILD\_SKIP* If defined, the buildworld, installworld, and distribution stages of the [chroot(8)](/chroot/8.md) build environment setup are skipped. This is intended solely for cases where the [chroot(8)](/chroot/8.md) userland are provided by alternate means. - *SRC\_UPDATE\_SKIP* Set to a non-empty value to prevent checkout or update of */usr/src* within the [chroot(8)](/chroot/8.md). This is intended for use only when */usr/src* is expected to exist by alternative means. - *PORTS\_UPDATE\_SKIP* Set to a non-empty value to prevent checkout or update of */usr/ports* within the [chroot(8)](/chroot/8.md). This is intended for use only when */usr/ports* is expected to exist by alternative means. - *NOPKGBASE* Include legacy tarball distribution sets for use on the install media, instead of base system packages. - *PKG\_CMD* A path to the pkg(8) executable to use when installing packages in release images as a non-root user. - *PKG\_REPOS\_DIR* An optional path to a directory containing pkg(8) repository configuration files. These configuration files will be used when installing packages in release images as a non-root user. - *PKG\_REPO\_NAME* The name of the repository configuration to use when installing packages in release images as a non-root user. ## EMBEDDED BUILDS The following *release.conf* variables are relevant only to release builds for embedded systems: - *EMBEDDEDBUILD* Set to a non-null value to enable functionality for embedded device release builds. When set, *WITH\_DVD* is unset. Additionally, *EMBEDDED\_TARGET* and *EMBEDDED\_TARGET\_ARCH* must also be defined. When the build environment is created, *release.sh* runs a separate build script located in an architecture-specific directory in *src/release/${EMBEDDED\_TARGET}/*. - *EMBEDDEDPORTS* Set to the list of any ports that are required for the target device in the format of *category/port*. - *EMBEDDED\_TARGET* When set, its value is passed to [make(1)](/make/1.md) to set the *TARGET* (value of **uname** **-m**) to cross build the target userland. - *EMBEDDED\_TARGET\_ARCH* When set, its value is passed to [make(1)](/make/1.md) to set the *TARGET\_ARCH* (value of **uname** **-p**) to cross build the target userland. ## VIRTUAL MACHINE DISK IMAGES The following *release.conf* variables are relevant only to virtual machine disk image builds: - *WITH\_VMIMAGES* Set to a non-null value to build virtual machine disk images as part of the release build. *WITH\_VMIMAGES* may also be specified as an environment variable passed to [make(1)](/make/1.md). - *WITH\_COMPRESSED\_VMIMAGES* Set to a non-null value to compress the virtual machine disk images with [xz(1)](/xz/1.md) as part of the **install** [make(1)](/make/1.md) target. Note that compressing virtual machine disk images may take a very long time on some systems. - *VMBASE* Set to change the name of the resulting virtual machine disk image file. The default value is *vm*. - *VMSIZE* Set to change the size of the virtual machine disk capacity. The default value is *20g*. See [makefs(8)](/makefs/8.md) for valid values. Virtual machine disk images are, by default, created as sparse images. When *WITH\_COMPRESSED\_VMIMAGES* is used, the resulting files compressed with [xz(1)](/xz/1.md) compress to roughly the same size, regardless of the specified disk image size. - *VMFS* (Deprecated.) Set to specify which of the filesystem(s) listed in *VMFSLIST* is linked to the historical non-filesystem-labelled file name. Valid values are *ufs* and *zfs*. The default value is *ufs*. - *VMFSLIST* Set to specify the list of file system types to build images for. Valid values are one or both of *ufs* and *zfs*. The default value is *ufs* *zfs*. - *VMFORMATS* Set to the target virtual disk image format(s) to create. By default, the *vhdf*, *vmdk*, *qcow2*, and *raw* formats are created. See [mkimg(1)](/mkimg/1.md) for valid format values. For a list of supported *VMFORMATS* values (including cloud hosting provider formats) along with a brief description, run: ``` cd /usr/src make -C release list-vmtargets ``` ## CLOUD HOSTING MACHINE IMAGES The FreeBSD release build tools support building virtual machine images for various cloud hosting providers, each with their own specific configuration to include support for each hosting provider by default. The following [make(1)](/make/1.md) environment variables are supported: - *CLOUDWARE* Set to a list of one or more cloud hosting providers, enclosed in quotes. Requires *WITH\_CLOUDWARE* to also be set. - *WITH\_CLOUDWARE* Set to a non-empty value to enable building virtual machine images for various cloud hosting providers. Requires *CLOUDWARE* to also be set. Additionally, the *CLOUDWARE* and *WITH\_CLOUDWARE* variables can be added to *release.conf*, and used in conjunction with *release.sh*. For a list of supported *CLOUDWARE* values, run: ``` cd /usr/src make -C release list-cloudware ``` ## OCI IMAGES The FreeBSD release build tools have experimental support for building Open Container Initiative (OCI) format container base images. This is enabled using a *release.conf* variable: - *WITH\_OCIIMAGES* Set to a non-null value to build OCI base images. ## MAKEFILE TARGETS The release makefile (*src/release/Makefile*) is fairly abstruse. Most developers will only be concerned with the **release** and **install** targets. - **release** Meta-target to build all release media and distributions applicable to this platform. - **install** Copy all produced release media to *${DESTDIR}*. - **cdrom** Builds installation CD-ROM images. This may require the [md(4)](/md/4.md) (memory disk) device driver be present in the kernel (either by being compiled in or available as a module). This target produces files called *disc1.iso* and *bootonly.iso* as its output. - **dvdrom** Builds installation DVD-ROM images. This may require the [md(4)](/md/4.md) (memory disk) device driver be present in the kernel (either by being compiled in or available as a module). This target produces the *dvd1.iso* file as its output. - **memstick** Builds an installation memory stick image named *memstick.img*. Not applicable on all platforms. Requires that the [md(4)](/md/4.md) (memory disk) device driver be present in the kernel (either by being compiled in or available as a module). - **mini-memstick** Similar to **memstick**, with the exception that the installation distribution sets are not included. - **ftp** Creates a directory named *ftp* containing the distribution files used in network installations and suitable for upload to an FTP mirror. - **vm-image** Creates virtual machine disk images in various formats. The **vm-image** target requires the *WITH\_VMIMAGES* [make(1)](/make/1.md) environment variable to be set to a non-null value. - **vm-cloudware** Builds FreeBSD virtual machine images for various cloud hosting providers. See "CLOUD HOSTING MACHINE IMAGES" for implementation details. - **list-cloudware** Displays the list of valid *CLOUDWARE* values. - **list-vmtargets** Displays the list of valid *VMFORMATS* and *CLOUDWARE* values. Major subtargets called by targets above: - **packagesystem** Generates all the distribution archives (base, kernel, ports, doc) applicable on this platform. - **disc1** Builds a bootable installation system containing all the distribution files packaged by the **packagesystem** target, and suitable for imaging by the **cdrom**, **dvdrom** and **memstick** targets. - **reldoc** Builds the release documentation. This includes the release notes, hardware guide, and installation instructions. Other documentation, such as the Handbook, is built during the **base.txz** target invoked by **packagesystem**. ## ENVIRONMENT Optional variables: - OSRELEASE Optional base name for generated media images when invoking the **install** target (e.g., FreeBSD-12.1-RELEASE-amd64). Defaults to the output of **\`uname** **-s\`-\`uname** **-r\`-\`uname** **-p\`** within the chroot. - WORLDDIR Location of a directory containing the src tree. By default, the directory above the one containing the makefile (*src*). - PORTSDIR Location of a directory containing the ports tree. By default, */usr/ports*. If it is unset or cannot be found, ports will not be included in the release. - NOPORTS If defined, the Ports Collection will be omitted from the release. - NOSRC If set, do not include system source code in the release. - TARGET The target hardware platform. This is analogous to the “**uname** **-m**” output. This is necessary to cross-build some target architectures. For example, cross-building for ARM64 machines requires TARGET\_ARCH=aarch64 and TARGET=arm64. If not set, TARGET defaults to the current hardware platform. - TARGET\_ARCH The target machine processor architecture. This is analogous to the “**uname** **-p**” output. Set this to cross-build for a different architecture. If not set, TARGET\_ARCH defaults to the current machine architecture, unless TARGET is also set, in which case it defaults to the appropriate value for that platform. Typically, one only needs to set TARGET. ## FILES - */scratch* - */usr/doc/Makefile* - */usr/doc/share/mk/doc.project.mk* - */usr/ports/Mk/bsd.port.mk* - */usr/ports/Mk/bsd.sites.mk* - */usr/share/examples/etc/make.conf* - */usr/src/Makefile* - */usr/src/Makefile.inc1* - */usr/src/release/Makefile* - */usr/src/release/Makefile.vm* - */usr/src/release/release.sh* - */usr/src/release/release.conf.sample* - */usr/src/release/tools/\*.conf* - */usr/src/release/tools/vmimage.subr* ## EXAMPLES The following sequence of commands can be used to build a “-CURRENT snapshot”: ``` cd /usr git clone -b main https://git.freebsd.org/src.git src cd src make buildworld buildkernel cd release make obj make release make install DESTDIR=/var/freebsd-snapshot ``` After running these commands, all produced distribution files (tarballs for FTP, CD-ROM images, etc.) are available in the */var/freebsd-snapshot* directory. The following sequence of commands can be used to build a “-CURRENT snapshot” in a clean environment, including ports and documentation: ``` cd /usr/src/release sh release.sh ``` Optionally, a configuration file can be used to customize the release build: ``` cd /usr/src/release sh release.sh -c $HOME/release.conf ``` Configuration files specific to various supported embedded systems, such as the Raspberry Pi, exist in the directory corresponding to the *TARGET* [make(1)](/make/1.md) variable. For example, to build an image for 64-bit Raspberry Pis: ``` cd /usr/src/release sh release.sh -c arm64/RPI.conf ``` After running these commands, all prepared release files are available in the */scratch* directory. The target directory can be changed by specifying the *CHROOTDIR* variable in release.conf. ## COMPATIBILITY The reldoc target was removed in commit f61e92ca5a23, and DOCDIR, DOCBRANCH, DOC\_UPDATE\_SKIP, and NODOC are therefore no longer supported. ## SEE ALSO [cc(1)](/cc/1.md), [git(1)](/git/1.md) (*ports/devel/git*), [install(1)](/install/1.md), [make(1)](/make/1.md), [mkimg(1)](/mkimg/1.md), [uname(1)](/uname/1.md), [md(4)](/md/4.md), [make.conf(5)](/make.conf/5.md), [build(7)](/build/7.md), [ports(7)](/ports/7.md), [chroot(8)](/chroot/8.md), [mtree(8)](/mtree/8.md), [sysctl(8)](/sysctl/8.md) *FreeBSD Release Engineering*, https://docs.freebsd.org/en/articles/freebsd-releng/. *FreeBSD Developers' Handbook*, https://docs.freebsd.org/en/books/developers-handbook/. ## HISTORY FreeBSD 1.x used a manual checklist, compiled by Rod Grimes, to produce a release. Apart from being incomplete, the list put a lot of specific demands on available file systems and was quite torturous to execute. As part of the FreeBSD 2.0 release engineering effort, significant effort was spent getting *src/release/Makefile* into a shape where it could at least automate most of the tediousness of building a release in a sterile environment. For the FreeBSD 9.0 release, *src/release/Makefile* was overhauled and the wrapper script *src/release/generate-release.sh* introduced to support the introduction of a new installer. For the FreeBSD 9.2 release, *src/release/release.sh* was introduced to support per-build configuration files. *src/release/release.sh* is heavily based on the *src/release/generate-release.sh* script. At near 1000 revisions spread over multiple branches, the [git(1)](/git/1.md) log of *src/release/Makefile* contains a vivid historical record of some of the hardships release engineers go through. ## AUTHORS *src/release/Makefile* was originally written by Rod Grimes, Jordan Hubbard, and Poul-Henning Kamp. This manual page was originally written by Murray Stokely ⟨*murray@FreeBSD.org*⟩. It was updated by Nathan Whitehorn ⟨*nwhitehorn@FreeBSD.org*⟩ to include the *generate-release.sh* script used for the FreeBSD 9.0 release cycle. It was later updated by Glen Barber ⟨*gjb@FreeBSD.org*⟩ to include the *release.sh* script used for the FreeBSD 9.2 release cycle.