Intermittent HTTP/HTTPS access over ZeroTier with firmware 20251204

[Tofolmp]

Hello,
We are experiencing an intermittent remote access issue with one of our LogicMachine 5 Lite devices and would like to know whether this behaviour is already known.
Hardware

• LogicMachine 5 Lite (i.MX6)
  

Current firmware

• Firmware: 20251204
  
• Linux kernel: 5.10.247
  

Issue description
The LogicMachine is accessed remotely through a private ZeroTier network.
The behaviour is always the same:

• HTTP/HTTPS access via the ZeroTier IP works normally for some time.
  
• After an unpredictable period, the web interface stops responding.
  
• The browser eventually reports that the device is not responding or the connection times out.
  
• A few minutes later, without any intervention, the web interface starts working again.
  

The problem is completely intermittent.
Tests already performed
ZeroTier

• Service enabled
  
• Status: OK
  
• Port: 9993
  
• Private network
  
• DIRECT connection (not relayed)
  

Connectivity

• Ping through ZeroTier usually works, although larger ICMP packets show intermittent packet loss.
  
• TCP port 80 is reachable.
  
• TCP port 443 is reachable.
  
• ETS6 continues communicating through the LogicMachine KNX/IP interface without interruption, even while the web interface is no longer responding.
  

Therefore:

• ZeroTier remains connected.
  
• KNX/IP communication continues working correctly.
  
• The issue appears to affect only HTTP/HTTPS access through ZeroTier.
  

Local access
When connected to the local LAN:

• The web interface is always accessible.
  
• No communication problems have been observed.
  

The issue only appears when accessing the LogicMachine through ZeroTier.
System load
Average load:
0.09 / 0.09 / 0.09
The LogicMachine is almost idle, so this does not appear to be a resource issue.
Comparison with another installation
We have another installation with very similar characteristics:

• Same LogicMachine 5 Lite hardware
  
• Same ZeroTier network
  
• Starlink Internet connection
  
• Remote access through ZeroTier
  

This second installation has been operating without any issues.
Working LogicMachine

• Firmware: 20250813
  
• Linux kernel: 5.10.240
  
• Uptime: more than 57 days
  
• Stable HTTP/HTTPS access over ZeroTier
  

Problematic LogicMachine

• Firmware: 20251204
  
• Linux kernel: 5.10.247
  
• Intermittent HTTP/HTTPS access over ZeroTier
  

At the moment, the firmware/kernel version is the only significant difference we have identified.
Additional observation
We also noticed one difference in the HTTP server configuration:
Working LogicMachine

• HTTP and HTTPS enabled.
  

Problematic LogicMachine

• HTTPS only, with automatic HTTP → HTTPS redirection.
  

We have intentionally not modified this setting yet in order to avoid introducing additional variables during troubleshooting.
The LogicMachine is connected to the Internet through a UniFi UDM Pro and Starlink.
We have already reviewed the gateway configuration (firewall, IDS/IPS, VPN, routing, CyberSecure, etc.) and did not find anything unusual.
Question
Is this a known issue with firmware 20251204 or Linux kernel 5.10.247?
Have you received any similar reports regarding intermittent HTTP/HTTPS access over ZeroTier?
Before downgrading the firmware to 20250813, we would like to know whether this behaviour is already known or if you recommend any additional diagnostic procedure.
If necessary, I can provide system logs, perform any additional tests you recommend, or provide any further information required.
Thank you very much.