OAI Build Procedures

This page is valid on tags starting from 2019.w09.

Soft Modem Build Script

OAI softmodem sources, which aim to implement 3GPP compliant UEs, eNodeB and gNodeB can be downloaded from the Eurecom gitlab repository.

Sources come with a build script build_oai located at the root of the openairinterface5g/cmake_targets directory. This script is developed to build the oai binaries (executables,shared libraries) for different hardware platforms, and use cases.

The main oai binaries, which are tested by the Continuous Integration process are:

  • The LTE UE: lte-uesoftmodem

  • The 5G UE: nr-uesoftmodem

  • The LTE eNodeB: lte-softmodem

  • The 5G gNodeB: nr-softmodem

  • The LTE PHY simulators: dlsim and ulsim

  • The 5G PHY simulators: nr_dlschsim nr_dlsim nr_pbchsim nr_pucchsim nr_ulschsim nr_ulsim polartest smallblocktest ulsim ldpctest

Running the build_oai script also generates some utilities required to build and/or run the oai softmodem binaries:

  • con2uedata: a binary used to build the UE data from a configuration file. The created file emulates the sim card of a 3GPP compliant phone.

  • nvram: a binary used to build UE (IMEI…) and EMM (IMSI, registered PLMN) non volatile data.

  • rb_tool: radio bearer utility

  • genids T Tracer utility, used at build time to generate T_IDs.h include file. This binary is located in the T Tracer source file directory .

The build system for OAI uses cmake which is a tool to generate makefiles. The build_oai script is a wrapper using cmake, make and standard linux shell commands to ease the oai build and use . The file describing how to build the executables from source files is the CMakeLists.txt, it is used as input by cmake to generate the makefiles.

The oai softmodem supports many use cases, and new ones are regularly added. Most of them are accessible using the configuration file or the command line options and continuous effort is done to avoid introducing build options as it makes tests and usage more complicated than run-time options. The following functionalities, originally requiring a specific build are now accessible by configuration or command line options:

  • s1, noS1

  • all simulators as the rfsimulator, the L2 simulator, with exception of PHY simulators, which are distinct executables.

Calling the build_oai script with the -h option gives the list of all available options, but a process to simplify and check the requirements of all these options is on-going. Check the table At the end of this page to know the status of buid_oai options which are not described hereafter.

Building PHY Simulators

Detailed information about these simulators can be found in this dedicated page

Building UEs, eNodeB and gNodeB Executables

After downloading the source files, a single build command can be used to get the binaries supporting all the oai softmodem use cases (UE and [eg]NodeB):

cd <your oai installation directory>/openairinterface5g/
source oaienv
cd cmake_targets/
./build_oai -I -w USRP --eNB --UE --nrUE --gNB

  • The -I option is to install pre-requisites, you only need it the first time you build the softmodem or when some oai dependencies have changed.

  • The -w option is to select the radio head support you want to include in your build. Radio head support is provided via a shared library, which is called the “oai device” The build script creates a soft link from liboai_device.so to the true device which will be used at run-time (here the USRP one,liboai_usrpdevif.so . USRP is the only hardware tested today in the Continuous Integration process. The RF simulatorRF simulator is implemented as a specific device replacing RF hardware, it can be specifically built using -w SIMU option, but is also built during any softmodem build.

  • --eNB is to build the lte-softmodem executable and all required shared libraries

  • --gNB is to build the nr-softmodem executable and all required shared libraries

  • --UE is to build the lte-uesoftmodem executable and all required shared libraries

  • --nrUE is to build the nr-uesoftmodem executable and all required shared libraries

You can build any oai softmodem executable separately, you may not need all of them depending on your oai usage.

After completing the build, the binaries are available in the cmake_targets/ran_build/build directory. A copy is also available in the target/bin directory, with all binaries suffixed by the 3GPP release number, today .Rel15.

Issue when building nasmeh module

A lot of users and contributors have faced the issue: nasmesh module does not build.

The reason is that the linux headers are not properly installed. For example:

$ uname -r
4.4.0-145-lowlatency
$ dpkg --list | grep 4.4.0-145-lowlatency | grep headers
ii  linux-headers-4.4.0-145-lowlatency         4.4.0-145.171

In my example it is properly installed.

Check on your environment:

$ uname -r
your-version
$ dpkg --list | grep your-version | grep headers
$

Install it:

$ sudo apt-get install --yes linux-headers-your-version

On CentOS or RedHat Entreprise Linux:

$ uname -r
3.10.0-1062.9.1.rt56.1033.el7.x86_64
$ yum list installed | grep kernel | grep devel
kernel-devel.x86_64              3.10.0-1062.9.1.el7         @rhel-7-server-rpms
kernel-rt-devel.x86_64           3.10.0-1062.9.1.rt56.1033.el7

If your kernel is generic, install kernel-devel package: sudo yum install kernel-devel

In most case, your kernel is real-time. Install kernel-rt-devel package: sudo yum install kernel-rt-devel

Building Optional Binaries

Telnet Server

The telnet server can be built with the --build-lib telnetsrv option, after building the softmodem or while building it.

./build_oai -I -w USRP --eNB --UE --build-lib telnetsrv

or

./build_oai  --build-lib telnetsrv

You can get documentation about the telnet server here

Other optional libraries

Using the help option of the build script you can get the list of available optional libraries. Those which haven’t been mentioned above are known to need more tests and documentation.

./build_oai  --build-lib all will build all available optional libraries.

build_oai options

Option

Status

Description

-h

maintained

get help

-c

maintained

erase all previously built files for this target before starting the new build.

-C

maintained, needs improvement

erase all previously built files for any target before starting the new build.

–verbose-compile

maintained

get compilation messages, as when running make or gcc directly.

–cflags_processor

maintained

used to pass options to the compiler.

–clean-kernel

unknown

no code in the script corresponding to this option

–install-system-files

maintained

install oai built binaries in linux system files repositories

-w

maintained and tested in CI for USRP device

build corresponding oai device and create the soft link to enforce this device usage at run-time

–phy_simulators

maintained, tested in CI

build all PHY simulators, a set of executables allowing unitary tests of LTE and 5G channel implementation within oai.

–core_simulators

-s

–run-group

-I

maintained, tested in CI

install external dependencies before starting the build

–install-optional-packages

maintained

install optional packages, useful for developing and testing. look at the check_install_additional_tools function in cmake_targets/tools/build_helper script to get the list

-g

maintained

Specifies the level of debugging options used to build the binaries. Available levels are Release, RelWithDebInfo, MinSizeRe and Debug. If -g is not specified, Release is used, if -g is used without any level, Debug is used.

-G

maintained

Display Cmake debugging messages

–eNB

maintained and tested in CI

build lte-softmodem the LTE eNodeB

–UE

maintained and tested in CI

build lte-uesoftmodem the LTE UE

–gNB

maintained and tested in CI

build nr-softmodem the 5G gNodeB

–nrUE

maintained and tested in CI

build nr-uesoftmodem the 5G UE

–usrp-recplay

deprecated

use the USRP configuration parameters to use the record player.

–build-lib

maintained

build optional shared library(ies), which can then be loaded at run time via command line option. Use the –help option to get the list of supported optional libraries. all can be used to build all available optional libraries.

–UE-conf-nvram

maintained

Specifies the path to the input file used by the conf2uedata utility. defaults to openair3/NAS/TOOLS/ue_eurecom_test_sfr.conf

–UE-gen-nvram

maintained

Specifies the path where the output file created by the conf2uedata utility will be placed. Defaults to target/bin

-V

deprecated

Used to build with support for synchronization diagram utility. This is now available via the T-Tracer and is included if T-Tracer is not disabled.

–build-doxygen

unknown

build doxygen documentation, many oai source files do not include doxygen comments

–disable-deadline –enable-deadline –disable-cpu-affinity

deprecated

These options were used to activate or de-activate specific code depending on the choice of a specific linux scheduling mode. This has not been tested for a while and should be implemented as configuration options

–disable-T-Tracer

maintained, to be tested

Remove T_Tracer and console LOG messages except error messages.

–ue-autotest-trace –ue-timing –ue-trace

deprecated

Were used to enable conditional code implementing debugging messages or debugging statistics. These functionalities are now either available from run-time options or not maintained.

–build-eclipse

unknown

oai wiki home

oai softmodem features

running the oai softmodem