schroot

Lightweight virtualisation tool

Features

• Uses standard Unix chroot(2) to run programs in virtual environments
• Create named environments for fast and easy access
• Run a command or login shell in the virtual environment
• Mounts filesystems from the host in the virtual environment to provide seamless access to user data
• Change to another user or to root (uses PAM for authentication and authorisation, and like sudo can provide password authentication or passwordless access)
• Switch to a different system in the virtual environment, for example a 32-bit environment on a 64-bit host system
• Run entirely different architectures in the virtual environment, for example a PowerPC, ARM or MIPS platform on an amd64 host system--no need to cross-compile when you can run the host directly
• Snapshotting, including use of Btrfs and union filesystems, to provide clean copies of the virtual environment
• Session management--create persistent or temporary named copies of a virtual environment
• All the above may be done in parallel with multiple users

Supported platforms

• FreeBSD 10.2
• Linux

Build Dependencies

• An ISO C++11 compiler (Clang++ ≥ 3.4 or GCC ≥ 4.8 are recommended)
• The libraries and tools listed in the table below

Dependency	Version	When required	Debian	FreeBSD
C++ compiler	[C++11]	Build	build-essential	N/A (base system)
CMake	≥ 3.2.0	Build	cmake	cmake
Boost	≥ 1.54	Build, Run	libboost-all-dev	boost-all
PAM	≥ 1.1.8	Build, Run	libpam0g-dev	N/A (base system)
troff		(Build) [git]	groff	groff
gettext	≥ 0.16	(Build, Run)	gettext	gettext
Doxygen	≥ 1.8	(Build) [git]	doxygen	doxygen
po4a	≥ 0.40	(Build) [git]	po4a	po4a
googletest	≥ 1.7	(Build tests)	libgtest-dev	googletest

Optional dependencies are enclosed with parentheses in the "when required" column.

Note that the versions listed are the minimum versions being actively tested and supported. Older versions may work, or may work with minor effort, but have not been tested.

Building and installation

Debian

Debian and derivative systems do not provide a precompiled googletest library. Build a version for the schroot build with, for example:

mkdir build
cd build
mkdir gtest
(
  cd gtest
  cmake /usr/src/gtest
  make VERBOSE=1
)

And then build with:

cmake -DGTEST_ROOT="$(pwd)/gtest" /path/to/schroot
make
fakeroot ctest -V

FreeBSD

export CMAKE_PREFIX_PATH=/usr/local
cmake /path/to/schroot
make
fakeroot ctest -V

Build customisation

After running CMake as above, run cmake -LH to see basic configurable options. The following basic options are supported:

• btrfs-snapshot=(ON|OFF) Enable support for btrfs snapshots (requires Btrfs)
• debug=(ON|OFF) Enable debugging messages
• default_environment_filter=REGEX Default environment filter
• doxygen=(ON|OFF) Enable doxygen documentation
• loopback=(ON|OFF) Enable support for loopback mounts
• nls=(ON|OFF) Enable national language support (requires gettext)
• pam=(ON|OFF) Enable support for PAM authentication (requires libpam)
• personality=(ON|OFF) Enable personality support (Linux only)
• test=(ON|OFF) Enable unit tests
• union=(ON|OFF) Enable support for union mounts
• unshare=(ON|OFF) Enable unshare support (Linux only)

CMake will autodetect and enable all available features by default, so these options are mostly useful for disabling features which are not required.

Run cmake -LA to see all settable options. CMAKE_INSTALL_PREFIX is the equivalent of the Autoconf --prefix option. Additionally, CMAKE_INSTALL_SYSCONFDIR, CMAKE_INSTALL_LOCALSTATEDIR, CMAKE_INSTALL_LIBDIR etc. provide the equivalent sysconfdir, localstatedir and libdir Autoconf options. It is also possible to set the distributor name with -Ddistributor.

Run make doc to make the doxygen documentation. Run ctest to run the testsuite.

Note that the testsuite should be run under fakeroot or real root in order to work correctly, due to it testing permissions from the perspective of the root user with root-owned files.

Configuration

See schroot.conf(5) and schroot-setup(5).

Running

See schroot(1).

Translation

If you would like to see the schroot messages output in your own language, please consider translating the pot file (po/schroot.pot). If you would like to see the schroot man pages in your own language, please consider translating the pot file (man/po/schroot-man.pot).