Detailed instructions for building FreeNAS can be found here.

The steps below are the short summary version.

• Operating System

  • For building FreeNAS, your build environment must be FreeBSD 11-STABLE r309771 or later.

• Free space

  • For building on a ZFS based system, you must have ~140GB space free.
  • For building on a UFS based system, you must have ~180GB space free.

• An amd64 capable processor. 16GB of memory, or an equal/greater amount of swap space, is also required.

• An internet connection for downloading source and packages

Note: All these commands must be run as root.

Install the dependencies:

# make bootstrap-pkgs

Download and assemble the source code:

# make checkout PROFILE=profile_type

Compile the source, then generate the .ISO:

# make release PROFILE=profile_type

The vaid profile types are "freenas" and "fn_head" (see the build/profiles directory). Instead of specifying PROFILE=profile_type, you can set the profile type in the file build/profiles/profile-setting (e.g. echo freenas9 > build/profiles/profile-setting).

Once the build completes successfully, you'll have release bits in the _BE directory. 😄

To update an existing FreeNAS instance that you are using for development purposes:

• make update
• make ports
• make reinstall-package package=freenas host=root@1.2.3.4

Where 1.2.3.4 is the IP address of your development platform. SSH will be used to push and install the new packages onto that host. (Note previous comment about setting the profile). PLEASE NOTE that this is an advanced development technique and may completely destroy your system if you don't know what you're doing.