DeviceShelf Blog
Practical how-tos around your home network — identify devices, spot intruders, keep an eye on things.
Before giving a device a fixed IPv4 address, confirm the right subnet, DHCP scope, and current address use. This order reduces the chance of creating an address conflict or losing access to the device.
Read more →A private Wi-Fi address can make a Mac appear under a different MAC address on a router. Check the network-specific setting and record the change before altering reservations or access rules.
Read more →A device can use the network normally and still not answer a ping-based discovery attempt. Learn what that result means and how to check it without treating it as proof of an outage.
Read more →A router can legitimately have more than one network identity. Learn how to compare the records before treating a second entry as an intruder or a scanning error.
Read more →A NAS can answer one kind of network check while its Home Assistant entity is unavailable. Work from the entity's evidence to a narrow, reversible test before changing the network.
Read more →A device on a second private subnet may be reachable through a router while local discovery cannot see it. Learn how to verify the path before changing firewall or scan settings.
Read more →A practical way to check whether a local IP address still belongs to the device you expect before changing a router setting or connecting to the wrong machine.
Read more →A router restart can briefly make devices look unavailable or away. Learn how to make an automation react to a meaningful transition instead of a recovery blip.
Read more →A router client list and a network scan answer different questions. Learn how to compare them without treating either one as a complete live inventory.
Read more →A practical way to decide whether an ESPHome problem is a defect, a missing capability, or a configuration question—and how to prepare a useful report.
Read more →A practical way to choose, test, and use MQTT device events in Home Assistant without turning routine network changes into a stream of noisy alerts.
Read more →A practical way to compare a router's client list with a network scan, understand why the counts differ, and build a reliable inventory without guessing.
Read more →A practical way to distinguish a NAS reboot from a network or service outage, collect useful evidence, and decide what to check next.
Read more →When a device does not receive a fresh DHCP lease, separate address assignment from DNS and service problems. This troubleshooting order keeps the evidence clear and avoids changing several network settings at once.
Read more →Three ways to list every device on your home network with its IP address, MAC address and name: the router's device list, the built-in tools on Mac, Windows and Linux, and a network scanner that does all of it in one pass.
Read more →You have a MAC address from your router list and want to know which device it belongs to. Here is what a MAC can and cannot tell you, how to look up the vendor, and how to get from vendor name to the actual device.
Read more →A practical walkthrough for seeing every device on your home Wi-Fi, working out what each one is, and telling an intruder from your own randomized-MAC phone. Covers the router list, MAC/OUI vendor lookup, hostnames, what to do if someone really is connected, and why a one-time check isn't enough.
Read more →What self-hosted network monitoring means, and how to run device discovery, uptime checks, and alerts on hardware you own without a cloud dashboard. Covers the tool-agnostic basics, running a monitor 24/7 headless, and keeping the data on your own network.
Read more →A step-by-step checklist for locking down a home or homelab network: router credentials, WPA3, guest networks for IoT, WPS and UPnP, exposed ports, firmware, and spotting unknown devices. Includes the free and tool-agnostic way to do each step.
Read more →A rotating, vendor-less MAC address on your network is almost always MAC randomization, a privacy feature in modern phones and laptops. Here is what it does, how to spot it, why it breaks vendor lookup and allow-lists, and how to identify the device anyway.
Read more →Found open ports after a scan and aren't sure which ones matter? This guide explains what an open port is, which are genuinely risky (Telnet, RDP, SMB, exposed databases), how to check the service behind each with nmap, and how to close or firewall the ones that shouldn't be open.
Read more →The built-in Windows commands, the free GUI scanners, and what each one actually shows you. A practical walk-through from arp -a to full device identification, security checks, and live per-device bandwidth.
Read more →How to scan your LAN on Linux two ways: nmap and arp-scan from the terminal, or a GUI when you'd rather read results than flags. Covers the capture permissions Linux needs and how to run DeviceShelf natively via AppImage, .deb or .rpm.
Read more →A practical walkthrough for inventorying the smart plugs, cameras, TVs, speakers and sensors on your LAN. Identify each one by MAC vendor, mDNS/SSDP announcements and open ports, then decide what belongs on a guest VLAN.
Read more →You want a push notification the moment an unknown device connects to your network. What routers offer out of the box, why randomized MAC addresses complicate things, and how to set up alerts that don't wear you down.
Read more →The 2025 cloud outages had a side effect people rarely plan for. The dashboards meant to explain the problem were down with it. The case for one small, self-hosted monitor.
Read more →A device you don't recognize showed up in your Wi-Fi. Here is how to find out what it is (MAC vendor lookup, hostname, open ports, mDNS names) and what to do if it really doesn't belong there.
Read more →The occasional guide, new features and release news, straight to your inbox. No spam, unsubscribe anytime.
