Version 0.26.1

Running

Operating and Managing Falco

Run Falco as a service

If you installed Falco by using the deb or the rpm package, you can start the service:

service falco start

Or, for systemd:

systemctl start falco

It works because systemd-sysv-generator wraps init.d scripts into systemd units.

You can also view the Falco logs using journalctl.

journalctl -fu falco

Run Falco manually

If you’d like to run Falco by hand, you can find the full usage description for Falco by typing:

falco --help
Are you looking for userpace instrumentation? Please see this page.

Run within Docker

Even using container images, Falco needs kernel headers installed on the host as prerequisite to correctly build the driver (the kernel module or the eBPF probe) on the fly. This step is not needed when a prebuilt driver is already available.

You can find instructions on how to install the kernel headers for your system under the Install section.

Falco ships a set of official docker images. The images can be used in two ways as follows:

Least privileged (recommended)

You cannot use the Least privileged mode with the eBPF probe driver unless you have at least Kernel 5.8, this is because --privileged is needed to do the bpf syscall. If you are running Kernel >= 5.8 you can pass --cap-add SYS_BPF to the docker run command in the step 2 and ignore the Install the kernel module section completely.

You can read more details about this here

This is how the Falco userspace process can be ran in a container.

Once the kernel module has been installed directly on the host system, it can be used from within a container.

  1. Install the kernel module:

    • You can use an official installation method directly on the host
    • Alternatively, you can temporarily use a privileged container to install the driver on the host:
    docker pull falcosecurity/falco-driver-loader:latest
    docker run --rm -i -t \
        --privileged \
        -v /root/.falco:/root/.falco \
        -v /proc:/host/proc:ro \
        -v /boot:/host/boot:ro \
        -v /lib/modules:/host/lib/modules:ro \
        -v /usr:/host/usr:ro \
        -v /etc:/host/etc:ro \
        falcosecurity/falco-driver-loader:latest
    

The falcosecurity/falco-driver-loader image just wraps the falco-driver-loader script. You can find more about its usage here

  1. Run Falco in a container using Docker with the principle of least privilege:

    docker pull falcosecurity/falco-no-driver:latest
    docker run --rm -i -t \
        --cap-add SYS_PTRACE --pid=host $(ls /dev/falco* | xargs -I {} echo --device {}) \
        -v /var/run/docker.sock:/var/run/docker.sock \
        falcosecurity/falco-no-driver:latest
    

If you are running Falco on a system with the AppArmor LSM enabled (e.g Ubuntu), you will also need to pass --security-opt apparmor:unconfined to the docker run command above.

You can verify if you have AppArmor enabled using the command below:

docker info | grep -i apparmor
Note that ls /dev/falco* | xargs -I {} echo --device {} outputs a --device /dev/falcoX option per CPU (ie. just the devices created by the Falco’s kernel module).

Fully privileged

To run Falco in a container using Docker with full privileges:

If you want to use Falco with the Kernel module driver

docker pull falcosecurity/falco:latest
docker run --rm -i -t \
    --privileged \
    -v /dev:/host/dev \
    -v /proc:/host/proc:ro \
    -v /boot:/host/boot:ro \
    -v /lib/modules:/host/lib/modules:ro \
    -v /usr:/host/usr:ro \
    -v /etc:/host/etc:ro \
    falcosecurity/falco:latest

Alternatively, you can use the eBPF probe driver:

docker pull falcosecurity/falco:latest
docker run --rm -i -t \
    --privileged \
    -e FALCO_BPF_PROBE="" \
    -v /dev:/host/dev \
    -v /proc:/host/proc:ro \
    -v /boot:/host/boot:ro \
    -v /lib/modules:/host/lib/modules:ro \
    -v /usr:/host/usr:ro \
    -v /etc:/host/etc:ro \
    falcosecurity/falco:latest

Other configurable options:

  • DRIVER_REPO - See the Installing the driver section.
  • SKIP_DRIVER_LOADER - Set this environment variable to avoid running falco-driver-loader when the falcosecurity/falco image starts. Useful when the driver has been already installed on the host by other means.

Hot Reload

This will reload the Falco configuration and restart the engine without killing the pid. This is useful to propagate new config changes without killing the daemon.

kill -1 $(cat /var/run/falco.pid)