Connecting to an MPU5
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Overview
How to physically connect a computer to an MPU5 and reach its Web Management Interface (WMI) for the first time.
This assumes the MPU5 already has an RF module and antennas installed and is powered on.
Manual Reference
Side Connectors and Cable Types
The MPU5 doesn't use ordinary connectors for most external cabling. Instead, it has several side connectors — keyed 22-Pin ports on the chassis — plus a handful of dedicated connectors elsewhere on the unit for power, antennas, and video.
Every cable that plugs into a side connector has a 22-Pin connector that's keyed so it only mates with a compatible port. If a cable is designed to work with more than one side connector, it's keyed so it fits all of them. Common side-connector cables:
| Cable | Connector Provided | Used For |
|---|---|---|
| CBL-DATA-2001 | RJ45 (Ethernet) receptacle | Connecting a management computer to configure the MPU5 |
| CBL-DATA-2003 | USB Type A female receptacle | USB keyboard, mouse, hub, or thumb drive |
| CBL-DATA-3003 | HDMI output | External monitor or TV |
| CBL-PTT-0015 | PTT headset connector | Push-to-talk headset |
Note: there are more side-connector cable options than these — CBL-DATA-3002 and CBL-AUD-2007 among them (see the Rapid Configuration Tool QSG, 03EN283, for the full lineup). The chassis diagram showing exactly which physical port pairs with which cable is image-only in the vendor manual — check the physical unit if you're not sure which side connector to use for a cable not listed above.
To connect a cable to a side connector:
- Locate the correct side connector for your cable.
- Align the key pins on the cable's 22-Pin connector with the key holes on the case, and push the key pins in.
- Twist the thumbscrew clockwise until the cable is firmly seated and sits flush with the case.
Note: if a cable won't mate, confirm you're using the correct side connector, that the key pins are aligned and the cable isn't upside down, and that neither the thumbscrew nor the connector is bent, damaged, or obstructed by debris.
Other Connectors (Not Side Connectors)
A few connectors live elsewhere on the chassis and aren't part of the keyed side-connector system:
| Location | Connector | Used For |
|---|---|---|
| Bottom | Circular 3-pin power connector | Battery or battery eliminator (CBL-PWR-0001 or CBL-PWR-0002 only — the MPU5 cannot be powered via PoE) |
| Top | 3x RF antenna ports (RP-TNC) | RF antennas — must match the RF band of the installed RF module |
| Top | GPS antenna port (SMA) | GPS antenna |
| Top | HD-BNC | Camera video input via CBL-VID-2001 (HD-SDI) — does not supply power to the camera |
| Top | Power Knob | Powering the unit on/off |
| Top | Zeroize latch | Erasing the security key (also resets the management password and disables Cloud Relay) |
Front Door vs. Back Door
Once you're physically connected, you need an IP address to reach the MPU5's WMI — and the MPU5 answers to two different kinds of address:
- Back door address (
10.3.1.254) — a universal address every MPU5 answers to, but only over a direct, local Ethernet connection. Your computer's NIC needs a10.3.1.xaddress on the same subnet to use it. This only gives you access to the one node your computer is physically plugged into — it will not reach other nodes across the MANET. - Front door address — the IP address assigned to that specific node (set on the Network Configuration Tab). This is the address other nodes and computers use to reach it across the network, including over the MANET/mesh — not just over a direct cable.
Note: the first time you connect to a brand-new or factory-reset MPU5, use the back door address (10.3.1.254), since no front-door/assigned IP has been set yet. Once the node has a front-door IP configured and is on your network, use that IP for ongoing remote management instead of the back door.
Connecting the MPU5 to a Management Computer
- Connect CBL-DATA-2001 to the DATA side connector on the MPU5.
- Plug one end of a standard RJ45 Ethernet cable into the Ethernet receptacle on CBL-DATA-2001.
- Plug the other end into an Ethernet port on your management computer.
Configuring Your Computer's IP Address
To talk to the MPU5, your computer's IP address needs to be in the same subnet as the address you're connecting to. For the back door address (10.3.1.254), give your computer an address such as 10.3.1.10 with a 255.255.255.0 subnet mask.
Windows:
- Right-click the Network icon in the taskbar and open Network and Sharing Center.
- Click your Ethernet connection, then Properties.
- Select Internet Protocol Version 4 (TCP/IPv4) and click Properties again.
- Choose Use the following IP address.
- Enter
10.3.1.10for IP address and255.255.255.0for subnet mask, then click OK.
Linux:
sudo ifconfig eth0 10.3.1.10/24
or
sudo ip addr add 10.3.1.10/24 dev eth0
Logging In to the Web Management Interface
- Open a web browser and go to
https://10.3.1.254. - Your browser will warn that the certificate isn't trusted — this is expected for the MPU5's self-signed cert. Click through it (in Chrome/Edge: Advanced → Proceed/Continue; in Firefox: Advanced → Accept the Risk and Continue).
- Once the page loads, enter the Management Password and click Authenticate.
Note: if the WMI page won't load, verify your computer's IP address and subnet mask, confirm all cables are seated properly, double-check you're browsing to 10.3.1.254 (not a front-door IP that hasn't been set yet), try a different supported browser, or reboot the node.