# Getting Started {#getting_started}

## Getting the Source Code {#getting_started_source}

~~~{.sh}
git clone https://github.com/spdk/spdk
cd spdk
git submodule update --init
~~~

## Installing Prerequisites {#getting_started_prerequisites}

The `scripts/pkgdep.sh` script will automatically install the bare minimum
dependencies required to build SPDK.
Use `--help` to see information on installing dependencies for optional components.

~~~{.sh}
sudo scripts/pkgdep.sh
~~~

Option --all will install all dependencies needed by SPDK features.

~~~{.sh}
sudo scripts/pkgdep.sh --all
~~~

## Building {#getting_started_building}

Linux:

~~~{.sh}
./configure
make
~~~

FreeBSD:
Note: Make sure you have the matching kernel source in /usr/src/

~~~{.sh}
./configure
gmake
~~~

There are a number of options available for the configure script, which can
be viewed by running

~~~{.sh}
./configure --help
~~~

Note that not all features are enabled by default. For example, RDMA
support (and hence NVMe over Fabrics) is not enabled by default. You
can enable it by doing the following:

~~~{.sh}
./configure --with-rdma
make
~~~

## Running the Unit Tests {#getting_started_unittests}

It's always a good idea to confirm your build worked by running the
unit tests.

~~~{.sh}
./test/unit/unittest.sh
~~~

You will see several error messages when running the unit tests, but they are
part of the test suite. The final message at the end of the script indicates
success or failure.

## Running the Example Applications {#getting_started_examples}

Before running an SPDK application, some hugepages must be allocated and
any NVMe and I/OAT devices must be unbound from the native kernel drivers.
SPDK includes a script to automate this process on both Linux and FreeBSD.
This script should be run as root. It only needs to be run once on the
system.

~~~{.sh}
sudo scripts/setup.sh
~~~

To rebind devices back to the kernel, you can run

~~~{.sh}
sudo scripts/setup.sh reset
~~~

By default, the script allocates 2048MB of hugepages. To change this number,
specify HUGEMEM (in MB) as follows:

~~~{.sh}
sudo HUGEMEM=4096 scripts/setup.sh
~~~

On Linux machines HUGEMEM will be rounded up to system-default huge page
size boundary.

All available params can be viewed by running

~~~{.sh}
scripts/setup.sh help
~~~

Example code is located in the examples directory. The examples are compiled
automatically as part of the build process. Simply call any of the examples
with no arguments to see the help output. If your system has its IOMMU
enabled you can run the examples as your regular user. If it doesn't, you'll
need to run as a privileged user (root).

A good example to start with is `build/examples/identify`, which prints
out information about all of the NVMe devices on your system.

Larger, more fully functional applications are available in the `app`
directory. This includes the iSCSI and NVMe-oF target.