Real-world Testing of the Watchdog Function in Industrial LTE Router: How to Achieve Second-Level Self-Recovery After Power Restart?
In Industrial Internet of Things (IIoT) scenarios, the stability of network equipment directly impacts production line continuity and data security. However, industrial sites often face challenges such as voltage fluctuations, electromagnetic interference, and extreme temperatures, leading to unexpected power outages or system crashes in routers. Traditional routers typically require manual intervention or lengthy self-checks after power restarts, whereas industrial-grade routers, equipped with built-in Watchdog functionality, can achieve second-level self-recovery after power restarts, becoming a key technology for ensuring industrial network stability. This article provides an in-depth analysis of the implementation principles and real-world testing effects of the Watchdog function, and recommends a proven industrial LTE router, the USR-G806w, to help enterprises address network interruption pain points.
A welding workshop in an automobile manufacturing enterprise once experienced a 3-minute power restart for its router, causing welding robots to stop operations and resulting in a single-incident loss exceeding 100,000 yuan. Similar scenarios are common in industrial settings:
Logistics sorting lines: AGV carts deviate from paths due to network interruptions, causing cargo collisions;
Energy monitoring systems: Sensor data interruptions lead to remote control failures, posing safety hazards;
Remote operations and maintenance: Equipment status cannot be uploaded in real-time, requiring engineers to conduct on-site troubleshooting and increasing maintenance costs.
Ordinary commercial routers require the following steps to restore services after power restarts:
Hardware self-checks: Inspecting memory, storage, and other hardware statuses;
System loading: Starting the operating system and network protocol stack;
Network reconnection: Re-obtaining IP addresses and establishing VPN tunnels.
The entire process takes 1-5 minutes and may fail to start due to hardware failures in extreme environments (e.g., high temperatures, high humidity).
The Watchdog is a hardware/software combined monitoring mechanism that detects system operation status through timers:
Hardware Watchdog: An independent timer chip from the CPU that forcibly restarts the system if it does not receive a "feed the dog" signal (e.g., heartbeat packet) within a specified time.
Software Watchdog: Monitoring task status through the operating system kernel or applications, triggering restarts or fault recovery.
Typical implementation process:
Initializing the Watchdog timer during system startup (e.g., setting a timeout of 5 seconds);
The main program periodically sending heartbeat signals (e.g., resetting the timer every 1 second);
If the system crashes (e.g., infinite loops, memory overflow), the heartbeat signal is interrupted, and the Watchdog triggers a restart.
Industrial LTE routers optimize the Watchdog function for industrial scenarios to achieve more reliable self-recovery:
Dual Watchdog mechanism: The hardware Watchdog monitors the overall system status, while the software Watchdog monitors critical processes (e.g., VPN, firewall), triggering restarts upon failures at any level.
Quick start technology: Streamlining the system startup process and prioritizing network service loading, with real-world testing showing that the USR-G806w restores network connections in just 8 seconds from power off.
Fault log recording: Recording restart reasons (e.g., voltage abnormalities, software crashes) for maintenance analysis.
Device: USR-G806w industrial LTE router (fully metal casing, IP30 protection rating);
Network environment: 4G LTE (China Mobile) + wired broadband dual-link backup;
Testing scenario: Simulating voltage fluctuations causing router power outages, recording restart times and business recovery statuses.
| Testing Item | Traditional Router | USR-G806w |
| Time from power off to system startup completion | 1 minute and 15 seconds | 12 seconds |
| Network reconnection time | 45 seconds (requires redialing) | 8 seconds (automatically switches to backup link) |
| Business recovery integrity | Partial session interruptions | No packet loss, continuous sessions |
Key Findings:
Dual-link backup advantage: The USR-G806w automatically switches to 4G networks when wired links are interrupted, ensuring uninterrupted business operations;
Hardware-accelerated startup: Utilizing Qualcomm chipsets and optimizing firmware startup processes, the system startup speed is increased by 80%;
Watchdog response speed: The hardware Watchdog timeout is set to 5 seconds, and the software Watchdog detection cycle is 1 second, ensuring rapid responses after failures.
A steel enterprise: After deploying the USR-G806w, the number of network interruptions in the blast furnace monitoring system due to voltage fluctuations decreased from 3 times per month to 0, reducing annual maintenance costs by 200,000 yuan;
Smart agriculture project: The USR-G806w deployed in fields automatically restarted and resumed data uploads after thunderstorms, preventing sensor data loss.
Hardware Watchdog: Prioritize selecting independent hardware Watchdog chips (e.g., CAT1024) to avoid software Watchdog failures due to system crashes;
Quick start technology: Confirm whether the device supports firmware optimization, CPU isolation, and other acceleration technologies;
Dual-link backup: Support automatic switching between wired and wireless multiple links to ensure uninterrupted business operations during single-link failures.
Protection rating: Select IP30 (dustproof) or higher protection ratings based on industrial site environments;
Temperature range: Ensure the device supports wide-temperature operation from -40℃ to 75℃ (e.g., the USR-G806w supports -20℃ to 70℃);
Anti-interference capability: Choose devices with electromagnetic compatibility (EMC) certifications to reduce failures caused by electromagnetic interference.
Remote operations and maintenance: Support cloud platform management (e.g., the USR-G806w is paired with the USR Cloud Platform) for remote configuration and firmware upgrades;
Fault alerts: Notify network abnormalities in real-time through SMS or email to shorten fault response times.
The USR-G806w is an industrial-grade dual-WAN port router launched by Jinan USR IOT Technology Co., Ltd., designed specifically for high-reliability network requirements:
Hardware configuration: Qualcomm chipset, dual Gigabit Ethernet ports, supporting 4G LTE full network compatibility;
Watchdog function: Built-in hardware Watchdog + software Watchdog, providing dual-layer protection to ensure system stability;
Quick recovery: Restores network connections in 8 seconds after power restarts and supports intelligent dual-link switching;
Industrial-grade design: Fully metal casing, IP30 protection, supporting wide-temperature operation from -20℃ to 70℃.
Typical application scenarios:
Smart manufacturing: Connecting PLCs, robots, and other equipment to ensure real-time transmission of production data;
Energy monitoring: Deployed in substations and wind farms for remote equipment management and data collection;
Smart logistics: Providing stable networks for AGV carts and sorting systems to avoid path deviation risks.
The Watchdog function in industrial LTE router is a core solution for addressing business interruptions after power restarts. Through hardware-level monitoring, quick start technology, and dual-link backup, the USR-G806w has helped hundreds of enterprises achieve "uninterrupted" networks. If you are facing network stability challenges, welcome to submit inquiries for customized solutions, making industrial networks smarter and more reliable.
