Introduction

A simple Docker container that will uses nmap to scan a set of servers on a regular interval and sends an email when ndiff detects a change.

Configuration

Store configuration files in an environment file, such as /etc/sysconfig/docker-nmap-scans, Example:

# TARGETS is a space separated list of targets passed to nmap to scan and
# supports all targets that nmap supports. Required.
TARGETS=host.example.com 192.0.2.1 198.51.100.0/24

# MAILTO is the email address ndiff results are sent to. Required.
MAILTO=user@example.com

# INTERVAL is the runtime in seconds between scans. Required.
INTERVAL=86400

# OPTIONS is the arguments passed to nmap. Optional, defaults to '-Pn'.
# OPTIONS=-Pn -T5 -p 22,80 -oA

# TZ is the timezone. Optional.
# TZ=Australia/Adelaide

# BASE_DIR is used by systemd service file and represents path this repo without
# trailing spaces. Required for sample systemd service file, otherwise ignored.
# BASE_DIR=/home/user/dockers/nmap-scans

Running

docker run -d --restart=on-failure -v /base_dir/scripts:/scripts -v /base_dir/results:/results --env-file=/etc/sysconfig/docker-nmap-scans --name=nmap-scans nmap-scans
docker logs -f nmap-scans

systemd

An example systemd service file and installation instructions. Alternative use the --restart Docker argument.

cp systemd-docker-nmap-scans.service /etc/systemd/system/docker-nmap-scans.service
systemctl enable docker-nmap-scans
systemctl start docker-nmap-scans
systemctl status docker-nmap-scans