# Periodic 502 Errors with Node-RED Version 2.2 - Need Help for Troubleshooting

**URL:** https://discourse.nodered.org/t/periodic-502-errors-with-node-red-version-2-2-need-help-for-troubleshooting/83634
**Category:** General
**Created:** [12 December 2023 10:56 UTC](https://discourse.nodered.org/t/periodic-502-errors-with-node-red-version-2-2-need-help-for-troubleshooting/83634 "2023-12-12T10:56:04Z")
**Posts on this page:** 1
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### Author: ![hnuzhoulin](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/hnuzhoulin/32/85755_2.png) [@hnuzhoulin](https://discourse.nodered.org/u/hnuzhoulin)
#### Post date: [13 December 2023 09:53 UTC](https://discourse.nodered.org/t/periodic-502-errors-with-node-red-version-2-2-need-help-for-troubleshooting/83634/8 "2023-12-13T09:53:27Z")

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It happened again, but this time I didn't rush to restart Node-RED. Instead, I verified if the data flow in the processes behind Node-RED was interrupted. Upon checking, I found that although the **CPU and load on the server hosting Node-RED were high** , it was **continuously processing data and successfully sending it to the destination**. The subsequent programs successfully received the data and wrote it into InfluxDB.

When I checked the monitoring again, I noticed that the number of **TCP connections had risen from 400 to over 4,000 in the last four hours**. All these new TCP connections were to Kafka. Here, Node-RED acts as a Kafka producer, so I couldn't find any useful information on the Kafka side. Looking back at the historical monitoring, I noticed that **each time there was a failure, there was this phenomenon of connection counts skyrocketing to over 4,000**.

During the failure, I was **able to SSH into** the server hosting Node-RED, and from other servers, **I could telnet to port 1880**. It seems that **only the dashboard was unusable**. The flows I have in Node-RED are quite simple, serving primarily a forwarding role. The exported files are as follows:

[flows202312131652.json](https://discourse.nodered.org/uploads/short-url/lyA9PWrszkxMW9xU3mHZlDedbXW.json) (60.1 KB)

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