IP and MAC addresses

The MAC address is the network hardware’s own permanent ID — twelve hex characters, usually written a4:83:e7:1b:2c:3d. It’s what the lab network sees, so it’s how a device gets recognized, allowed on a network, or found when it’s misbehaving.

The IP address is temporary. It’s handed out by whatever network the device is on that day, and it changes. Record the MAC; only record an IP if it’s a fixed one we assigned.

Nothing on this page needs a terminal. Every device has a click path, and the terminal command is there as an extra at the end of each section.

Read this first: the randomized-MAC trap

Phones, tablets, and headsets now invent a fake MAC address per Wi-Fi network by default, for privacy. The result: the address the network sees is not the address printed in the device’s settings, and MAC-based tracking quietly stops matching.

So for lab equipment on the lab network, record the device’s real MAC (the one in the About screen), and where the device offers the choice, switch that network to use the real one. The per-device instructions below say where the toggle is.

Windows 11

Point and click:

1. Settings → Network & internet
2. Click Wi-Fi (or Ethernet, if it’s plugged in)
3. Click the connection’s Properties (Wi-Fi: click the network name at the top)
4. Scroll down. You want two lines:
   • IPv4 address — the IP
   • Physical address (MAC) — the MAC

All adapters at once (useful on a workstation with Wi-Fi + Ethernet): Settings → Network & internet → Advanced network settings → Hardware and connection properties. Every adapter is listed with its Physical address (MAC).

Turn off randomization for a lab machine: Settings → Network & internet → Wi-Fi → Random hardware addresses → Off.

Terminal version: open Command Prompt or PowerShell and run ipconfig /all — the MAC is the “Physical Address” line under each adapter.

macOS

Point and click:

1. menu → System Settings
2. Network → click Wi-Fi (or your Ethernet/USB adapter)
3. Click Details… next to the connected network
4. TCP/IP tab → IPv4 Address (the IP)
5. Hardware tab → MAC Address

Terminal version:

networksetup -listallhardwareports    # every interface and its MAC
ipconfig getifaddr en0                # the IP of the Wi-Fi interface

iPhone and iPad

The device’s real MAC: Settings → General → About → Wi-Fi Address. That’s the one to record.

The IP on the current network: Settings → Wi-Fi → tap the ⓘ next to the connected network → IP Address.

The randomization toggle is on that same ⓘ screen: Private Wi-Fi Address. On lab iPads that we track on the network, turn it off for the lab network.

Android and Samsung Galaxy

Both values in one place: Settings → About phone → Status information — it lists the IP address and the Wi-Fi MAC address.

The per-network randomization setting: Settings → Connections → Wi-Fi → tap the gear next to the connected network → View more → MAC address type → choose Phone MAC instead of Randomized MAC.

Menu wording moves around between Android versions and manufacturers; “About phone → Status” is the one that has stayed put.

Meta Quest

The headset’s MAC: put the headset on → Settings → System → About. The MAC address is listed there.

Per-network: Settings → Wi-Fi → Saved Networks → tap your network → MAC address. Quest headsets randomize by default — switch this to Device MAC for the lab network, or the headset shows up as a different device every time it reconnects.

The IP: the same saved-network panel shows the address the headset was given.

You can also see the headset’s MAC in the Meta Horizon phone app under the headset’s device settings.

Over adb, if the headset is in Developer Mode:

adb shell ip addr show wlan0

HoloLens 2

Put the headset on → Settings → Network & Internet → Wi-Fi → select the connected network → Advanced options (labeled Hardware properties on some builds). Both the IPv4 address and the Physical address (MAC) are on that screen.

Linux (GNOME desktop)

1. Settings → Wi-Fi (or Network for a wired connection)
2. Click the gear icon next to the connection
3. The Details tab shows IPv4 Address and Hardware Address (the MAC)

Terminal version: ip addr for both, or nmcli device show for a per-interface breakdown.

FreeBSD and headless servers

No GUI — ifconfig lists every interface with its ether (MAC) and inet (IP) lines. On our headless fleet boxes that’s the only route, and it’s the same command on Linux with ip addr.

What to record in the inventory

• Wi-Fi MAC — the device’s real one, not a randomized address.
• Ethernet MAC — separately, if the machine has a wired port. They’re different addresses on the same machine.
• Whether the IP is static or DHCP. A DHCP address isn’t worth recording; a static one we assigned is.
• The hostname, if the machine has one on the fleet.

A MAC address identifies a device on our network but isn’t secret in any meaningful way. Treat it like the serial: fine inside the lab, not something to post publicly.