Base
Hardened build
minimal ports, security patches applied at build time
NetAlertX Network Presence Scanner
AWS
Networking
NetAlertX, a network presence scanner that continuously discovers every device on your network and tells you the moment an unknown one appears.
Overview
NetAlertX is an open source network presence scanner and asset discovery framework. It repeatedly sweeps the network it is attached to, builds an inventory keyed on each device's hardware address, and remembers everything it has ever seen: when a device first appeared, when it was last present, and how its presence has changed over time. When something new joins the network, or a device you rely on stops answering, it raises an alert through the channel you choose, from email and webhooks to MQTT and a range of push services.
Because it identifies devices by hardware address rather than by name or address alone, it keeps a stable picture of a network where addresses are handed out dynamically, and it enriches what it finds with vendor lookup and name resolution so the inventory reads as equipment rather than as numbers. It suits anyone who needs to know what is actually on a network rather than what is supposed to be: teams keeping an asset inventory honest, operators watching for equipment that should not be there, and anyone who wants presence history and change alerting for the devices they depend on.
Why the cloudimg image
cloudimg delivers NetAlertX fully installed with its scanner toolchain, web interface and database, so a working scanner answers the moment the instance boots. The image is secure by default, which matters a great deal for this product because upstream ships with its login switched off entirely and, when it is switched on, with a published default password: cloudimg removes that default, binds the application interface to the loopback address so it cannot be reached directly, fronts the web interface with an authenticating reverse proxy, and generates a password unique to each instance on its first boot, written to a file only the root user can read. No shared or default login exists anywhere in the image. Scanning is scoped to the instance's own network by default, so it never reaches beyond the network you deployed it into unless you choose to widen it. The base is fully patched with unattended security upgrades enabled, and every deployment is paired with a step by step deploy guide and backed by 24/7 cloudimg support.
Common uses
- Keeping a continuous inventory of every device on a network
- Alerting when an unknown device joins or a known device stops answering
- Presence history and change tracking for equipment you depend on
Key features
- Open source network presence scanner (GPL-3.0) that continuously discovers every device on your subnet, records each with IP, MAC, vendor, and hostname, and maintains a per-device presence timeline showing exactly when devices appear and disappear. Alerts notify you immediately via email, webhook, or other channels when a new device joins or a known device goes missing.
- Cloud hardened security posture: nginx HTTP Basic Auth with a bcrypt credential generated uniquely per instance at first boot protects the dashboard on a public IP. The scanner API is bound to loopback so the authentication gate cannot be bypassed. No default or shared passwords exist - credentials are created exclusively on your instance at launch time.
- Safe defaults with 24/7 cloudimg support: scans only the instance's own subnet by default and never reaches wider without an explicit configuration change. Lightweight SQLite data tier requires no external database. cloudimg provides round-the-clock technical support by email and chat for inventory review, alert tuning, scan-scope adjustment, and image updates.
See it running
Real screenshots taken while testing this image against its deployment guide.
Description
This is a repackaged open source software product wherein additional charges apply for cloudimg support services.
Overview
NetAlertX is the open source network presence scanner and intrusion-detection framework (the project formerly known as Pi.Alert). It repeatedly sweeps the network it is attached to, keeps a MAC-keyed inventory of every device it has ever seen, records a presence timeline for each one, and raises alerts when a new device appears or a known device goes missing. This image delivers NetAlertX fully installed from its pinned upstream release, so you can open the dashboard and start discovering devices within moments of launch.
Know Every Device On Your Network
NetAlertX discovers the devices on your subnet and records each one with its IP, MAC, vendor, hostname and a full presence history. The dashboard shows what is online now, what has been seen before, and when each device came and went, so an unfamiliar device joining the network is immediately visible. Per-device detail views, an events feed and a presence timeline turn a raw scan into an understandable picture of your network.
Alerting Built In
Configure notifications so a newly appearing device, a device going down, or a device coming back can reach you by email, webhook or one of the many supported notification channels. Tune which events matter, and let NetAlertX watch the network so you do not have to.
Hardened For A Public Cloud
NetAlertX's own login is disabled by upstream default and is not fit to be the boundary on a public IP, so this image puts an nginx HTTP Basic Auth sign-in in front of the whole dashboard, with a bcrypt credential generated uniquely on this instance at first boot. The scanner API is bound to loopback so that gate cannot be bypassed, and discovery is tuned for cloud virtual networks, where the usual ARP-based scan is unreliable. The image ships no known password: the credential is created on your instance, and nothing in the image knows it.
Scans Only What You Deploy It Into
By default NetAlertX scans only the subnet this instance sits in, resolved from the instance's own network interface at first boot. It never ships pointed at a wider network. Widening the scan is an explicit, documented choice, and you must only scan networks you own or are authorised to scan.
cloudimg Support
24/7 technical support by email and chat. Help with reading the inventory, tuning discovery and alerts, adjusting the scan scope, and keeping the image current.
Use Cases
Continuous discovery and inventory of the devices on a cloud or on-premises subnet. Intrusion awareness through alerts when an unexpected device joins the network. A presence timeline for auditing when devices are online.
All product and company names are trademarks or registered trademarks of their respective holders. Use of them does not imply any affiliation with or endorsement by them.
Related technologies
netalertxnetwork presence scannerdevice discoveryintrusion detectionnetwork monitoringpi.alertasset inventorymac address trackingsubnet scannernetwork security
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