About this task
You can install most libpcap-based application for use with Napatech libpcap interfaces using your distributions package manager.
Before you begin
If the user group napatech exists, you must have root privileges or be a member of the napatech group in order to use Napatech libpcap interfaces.
Dynamically linked applications should work the same whether installed before or after the Napatech libpcap.
Applications that are statically linked to libpcap must be recompiled and linked to the Napatech libpcap.
Ensure the use of the Napatech libpcap library
- By removing all other libpcap libraries from the system
- By forcing the application to use the Napatech libpcap library
To force an application to use the Napatech libpcap library, use one of these methods:
Set LD_PRELOAD in the environment for the application:
$ LD_PRELOAD=/opt/napatech3/lib/libpcap.so <app>
Set LD_LIBRARY_PATH in the environment for the application:
$ LD_LIBRARY_PATH=/opt/napatech3/lib/ <app>
Common applications are available from your distribution
Most common libpcap-based applications can be installed from your distributions default package repositories, and will run without further configuration. The package name will depend on the distribution.
For example, to install and run Wireshark on RHEL/CentOS:
$ sudo yum install wireshark-gnome $ wireshark
On Ubuntu and derivatives of Ubuntu, for example Mint, you must preload the Napatech libpcap shared library like this:
$ sudo apt-get install wireshark $ LD_PRELOAD=/opt/napatech3/lib/libpcap.so wireshark
Extra repositories for popular applications
If a package is not available from your distributions default package repositories, you might be able to add a repository that offer the package. The application homepage will often offer detailed instructions about how to add the repository and install the package.
For example, for Bro, the following is suggested for CentOS 7 at https://www.bro.org/download/packages.html:
$ cd /etc/yum.repos.d/ $ sudo wget http://download.opensuse.org/repositories/network:bro/CentOS_7/network:bro.repo $ sudo yum install bro
Package downloads for popular applications
For more information about installing and running Snort with SmartNICs and Napatech Software Suite, see DN-0666.
Application must be recompiled from source
If you need to compile the application yourself from source because no package is available for your distribution, the process will depend on the configure options of the application.
You should preferably link to the Napatech libpcap library to ensure the best match to the version of the Napatech libpcap.
The following examples use the installation directory prefix (--prefix) /opt/napatech3.
Most applications rely on Autoconf for configuration, and you will often find configure script options that allow you to select Napatech libpcap headers and libraries. You will usually have to specify linker flags.
libpcap configure script option
For example, for Tcpreplay there is a --with-libpcap option that helps the configure script find Napatech libpcap:
$ wget https://github.com/appneta/tcpreplay/releases/download/v4.1.0/tcpreplay-4.1.0.tar.gz $ tar xzf tcpreplay-4.1.0.tar.gz $ cd tcpreplay-4.1.0 $ ./configure --prefix=/opt/napatech3 LDFLAGS="-L/opt/napatech3/lib -lntapi -lntos" --with-libpcap=/opt/napatech3 --enable-dynamic-link --enable-force-inject $ make $ sudo make install
Even if a --with-libpcap option is available, you may also need to set compiler flags for the configure script to find Napatech libpcap. This is the case for recent versions of Tcpreplay:
$ wget https://github.com/appneta/tcpreplay/releases/download/v4.2.4/tcpreplay-4.2.4.tar.gz $ cd tcpreplay-4.2.4 $ ./configure --prefix=/opt/napatech3 CFLAGS=-I/opt/napatech3/include LDFLAGS="-L/opt/napatech3/lib -lntapi -lntos" --with-libpcap=/opt/napatech3 --enable-dynamic-link --enable-force-inject $ ...
Compiler and linker flags
For Tcpdump, you have to specify the Napatech libpcap using compiler and linker flags:
$ wget http://www.tcpdump.org/release/tcpdump-4.9.0.tar.gz $ tar xzf tcpdump-4.9.0.tar.gz $ cd tcpdump-4.9.0 $ ./configure --prefix=/opt/napatech3 CFLAGS=-I/opt/napatech3/include LDFLAGS="-L/opt/napatech3/lib -lntapi -lntos" $ make $ sudo make install
Some configure scripts does not allow compiler and linker flags as options. In that case, set the flags in the environment:
$ export CFLAGS=-I/opt/napatech3/include $ export LDFLAGS="-L/opt/napatech3/lib -lntapi -lntos" $ ./configure --prefix=/opt/napatech3 ... $ ...