So, I’m not a programmer but I am a network engineer that owns a consumer air conditioning product which is clearly using the whole blynk white label solution.
As a user I’ve been experiencing the same behavior as some of the devs here.
Symptom: My Air conditioner is online but my target temperature / fan speed commands don’t flow to the end device.
Aka - the blynk Device stops receiving pin write commands but is communicating with blynk cloud
Since I’m the end user and have never developed on blynk, all I can see are the customer facing apps and network packet captures.
From a network perspective I see 1x TLS stream and based on intervals between packets I can surmise two things
- Heartbeat/telemetry is configured to be sent on a 5-10s interval
- 1x Write command via a blynk server should trigger an immediate 1x TLS data packet to the IoT device (with a corresponding ack in return)
In the issue state, I continue to see the heartbeat/telemetry TLS traffic, but the write command TLS traffic (cloud-> IoT device) ceases entirely!
I can reliably reproduce by rebooting the router while leaving the device connected to wifi. Give it about 4 hours, and bam. Issue state.
To fix, I force disconnect it from Wi-Fi via the ap admin portal. When it reconnects a new session is created and all is fine.
Any idea what the primary cause of this behavior is?
Reading through the app store.reviews, users have been experiencing this issue for at least 10 months with this companies blynk based platform.
I collected tons of pcaps and session/state data from my virtualized OPNsense instance.
happy to provide more data via dm.