Dear Teltonika Support & Community,
We are operating a Teltonika RUTX50 in a live retail analytics environment. We’ve observed frequent mobile WAN disconnections, recurring DNS resolution issues, and suspect possible IP lease-related resets from the ISP. Stability is crucial in our deployment, and we’d appreciate guidance on how to address these behaviors.
What We Observed:
- The primary WAN interface is
mob1s1a1, using SIM1 on a 5G-NSA connection via 3Ireland. - Over the last 30 days, we’ve seen daily disconnects, typically at 20:07, where the WAN goes down and reselects the same mobile
- On 4 June 2025 at 08:17, the system reported the WAN down again, this time triggering a short-lived data outage and DNS disruption.
- These events correlate with
dnsmasqreinitializations, leading to temporary DNS resolution failures for dependent services.
What We Have Done:
- Extracted and analyzed
system.log, event logs, and failover logs. - Found no major hardware faults or modem driver issues.
- DNS instability appears tightly coupled with link resets or dynamic IP assignments from the ISP.
Our Questions:
- Is there a way to prevent the modem from requesting a new IP from the ISP after each drop or reconnect?
We’d prefer the interface to retain its existing IP where possible to maintain session continuity and DNS stability. - Failover Setup Advice:
We have a second SIM installed (SIM2). Could you recommend optimal failover settings to ensure smooth transition when SIM1 (mob1s1a1) becomes unstable or disconnects?
Specifically:
- How should we prioritize interfaces and tune the health check intervals?
- Should we use ping or DNS checks, and what values are best for balancing sensitivity vs false positives?
- Can failover be configured to be more proactive to reduce impact duration?
We are open to tweaking advanced settings (e.g. modem watchdog, IP passthrough handling, TTL adjustments) if needed.
Your technical insights or sample configuration suggestions would be greatly appreciated.
Kind regards,