Resolving Node-RED Firebase Errors on Siemens IOT2000 IOT2020

SIMATIC IOT2000 Series Hardware Reference

The SIMATIC IOT2000 family comprises two industrial IoT gateways built on Intel Quark (x86) SoC architecture and shipped with a custom Yocto-based Linux image. Both SKUs share the same Arduino Uno R3-compatible shield interface, a single 10/100 Mbit Ethernet port, two USB 2.0 host ports, and a 24 V DC power input.

Firmware V2.1.3 Image and Bundled Software Stack

Firmware V2.1.3 is one of the last released example images for the IOT2000 series and ships the following software versions out of the box:

The image is delivered as a writable .wic file (~250 MB) and must be flashed to the microSD card (IOT2020) or to the microSD / eMMC (IOT2040) using tools such as Win32DiskImager, balenaEtcher, or dd on Linux. Siemens provides the image and SHA-256 checksums via the SIMATIC IOT2000 example image support entry.

Problem Description: Firebase Nodes Will Not Initialise

Symptoms reported on firmware V2.1.3 with the example image installed unmodified:

• The node-red-contrib-firebase node throws an authentication or connection error on the first deploy.
• Node-RED logs a red exclamation mark in the Editor at the firebase (config) node.
• Edison/console output contains lines similar to:
  Firebase: FirebaseAuthError: There is no user record corresponding to this identifier.
  or
  ECONNREFUSED 127.0.0.1:9000
• The IOT2000 can reach the internet for npm install (palettete installation succeeds), but data exchanges terminate after 5-10 s.

These symptoms almost always fall into one of three categories: a local TCP/IP conflict, a misconfigured firebase database URL/secret, or a firewall/NAT issue on the upstream router. The first category is the most common on the IOT2000 because the device ships with a default address of 192.168.200.1 on the Ethernet interface - identical to the default subnet of many consumer SOHO routers (D-Link, TP-Link, certain Fritz!Box models, OpenWrt defaults).

Root Cause: IP Address Collision on 192.168.200.1

When the IOT2020 or IOT2040 is connected via Ethernet to a router that also uses 192.168.200.1/24 as its LAN prefix, the gateway (the router) and the IOT2000 appear at the same IPv4 address on the wire. The IOT2000's connman service binds the address, but routing becomes ambiguous: TCP SYN packets from the IOT2000 are returned to whichever device last sent an ARP reply for the address, which in practice is the router itself. The result is that:

1. The IOT2000 can no longer reach DNS (UDP 53) because DNS is offered by the router at 192.168.200.1, which the IOT2000 believes is itself.
2. Outbound TLS handshakes to *.firebaseio.com hang or fail, which surfaces as ETIMEDOUT in the firebase node.
3. When a USB WiFi NIC is also installed, the host's WLAN is also degraded because the IOT2000 begins responding to ARPs on the wired side and confuses the PC's IP stack - this matches the reported "I lose WiFi on my laptop when I connect the IOT2000" symptom.

Step-by-Step: Reconfigure the Ethernet Address and Restore Connectivity

Prerequisites

• SSH or serial console access to the IOT2000 (default user root, no password on the example image).
• Knowledge of the LAN prefix of the upstream router (for example 192.168.1.0/24).
• An unused IPv4 outside the router's DHCP pool (for example 192.168.1.50).

Procedure

1. Connect the IOT2000 to your PC over the Ethernet cable and access the console:
   ssh [email protected]
2. List the connman services to identify the Ethernet interface:
   connmanctl services
   Note the service identifier (typically *A0 ethernet_001122334455_cable).
3. Edit the persistent settings file (replace the MAC in the path):
   vi /var/lib/connman/ethernet_001122334455_cable/settings
4. Replace the IPv4 stanza with a static address on the production LAN:
   

   [ethernet_001122334455_cable]
   Name=Wired
   AutoConnect=true
   Modified=2018-04-12T08:32:01Z
   IPv4=192.168.1.50/255.255.255.0/192.168.1.1
   IPv6=off

5. Disable the WiFi client on the IOT2000 if you are not using it (recommended for deterministic routing):
   connmanctl disable wifi
6. Reboot and confirm:
   reboot
   After login:
   ip addr show dev eth0
ping -c 3 192.168.1.1
ping -c 3 sfo3.firebaseio.com

Configuring node-red-contrib-firebase (v1.1.1) Correctly

With IP connectivity restored, install the firebase palette node:

cd /usr/lib/node_modules
npm install [email protected] --save

Restart Node-RED:

systemctl restart node-red

In the Node-RED editor (http://<iot2000>:1880) drop a firebase config node and fill in the following parameters:

Minimum flow to push an S7 tag to Firebase every 5 s:

[{"id":"in.s7","type":"s7 in","z":"f1","endpoint":"192.168.1.20","mode":"single","variable":"DB1,REAL0","name":"TempPV"},
{"id":"fn.set","type":"function","z":"f1","name":"wrap","func":"msg.payload = { value: msg.payload, ts: Date.now() }; return msg;"},
{"id":"fb.out","type":"firebase out","z":"f1","firebase":"c1","childpath":"/machines/iot2000/temp","name":"Push"},
{"id":"c1","type":"firebase config","z":"","name":"iot2000-prod","firebase":"your-project.firebaseio.com","authType":"legacy","token":"<dbSecret>"}]

Hardware Selection: IOT2020, IOT2040, or IOT2050

For purely WiFi-based deployments a USB WiFi NIC based on the Realtek RTL8188CUS or Atheros AR9271 chipset is recommended; the Intel Quark kernel on firmware V2.1.3 does not include the brcmfmac or rt2x00 modules needed for some consumer adapters. Connect a USB hub if the WiFi NIC and a USB serial console dongle must coexist.

Network Architecture: Avoiding the 192.168.200.x Trap

The cleanest production deployment is to keep the IOT2000 on a dedicated industrial subnet, isolated from the office LAN, and route through a managed firewall that performs NAT to the upstream network. A recommended topology:

By moving the IOT2000 to a private subnet (10.10.10.0/24) the 192.168.200.1 collision is impossible by design, and the firewall can apply egress rules that allow only the Firebase FQDNs:

*.firebaseio.com        TCP 443
*.googleapis.com        TCP 443
sfo3-xxxx.firebaseio.com UDP 9553 (long-poll)

Verification Checklist

1. From the IOT2000 console: curl -v https://<project>.firebaseio.com/.json?print=pretty returns JSON, not an SSL error.
2. In Node-RED, the firebase (config) node has a green dot and no red exclamation.
3. Deploy a debug node downstream of a firebase in node pointing to /machines/iot2000/temp - it should emit the last value within 30 s.
4. From the Firebase console, the Realtime Database viewer shows the timestamped object {value: 23.7, ts: 1700000000000}.
5. Watch the connman log: journalctl -u connman -f - no DHCP renew errors and only one IPv4 on eth0.

Troubleshooting Matrix

Migration Path to the IOT2050

Siemens officially announced the phase-out of the IOT2000 line in 2021. New projects should use the SIMATIC IOT2050 with firmware V1.2.x or later, which provides:

• Container runtime (Docker/Podman) for running Node-RED as a signed image.
• Native OPC UA Pub/Sub over MQTT 5 - more efficient than the Firebase REST polling model.
• Updated Node.js 16 LTS and Node-RED 3.x compatibility.

The configuration procedure in this article applies to the IOT2050 by analogy: change the connman profile at /var/lib/connman/<iface>_<mac>_cable/settings, install node-red via the image, and deploy the same firebase flow with the newer node-red-contrib-firebase-modern package (which supports OAuth2 service accounts).

FAQ