[bug or feature?] Cellular data activated/preferred while WLAN/WiFi is enabled/in use

asked 2020-04-11 22:34:00 +0300

updated 2020-04-13 18:09:58 +0300

I guess it is better to file this as a single bug report, as the other question's title
is a bit in another direction.

Since a few weeks maybe months (? so probably due to SFOS 3.1 or 3.2) I sometimes have suddenly my data plan fully used. And only some time ago I noticed that the data icon in home screen was switching between WiFi and cellular data.
Disabling/enabling WiFi (or WLAN) fixed it. After that only wlan0 (respectively rmnet) had an IP address.

Only today I checked with ifconfig and traceroute and found two IP adresses assigned for wlan0 as well as rmnet_data. Also traceroute was confusing and had time outs.

So it seems that both data modules are working at the same time, which could be an enhancement (see above question/link).
But if so it should be announced and configurable!

Therefore I do see it as a bug:
that cellular data gets used even one have a good reception (at home) with WLAN signal.
I would not expect the phone to switch to cell data while wireless signal (WITH internet) is available. And even if so then it should switch back asap to WLAN!!!

adding some more info about my network:
I have a few APs all with same SSID and password so when moving at home sometimes the phone needs to switch AP.
I just noticed it happened again and this time the icon was switching, then stayed on WiFi (even cell data was used, checked with data counter)! So you did not even notice cell data was on.
The route was set to default set to my router, but had also entries for cell data dns servers.

This time I needed to switch off/on WLAN two times as on first off/on it was not resolved.

My guess:
race condition when enabling data services.
As it seems to happen when phone wants to switch WiFi AP but also has cell data on and tries to activate this.
It should not try to activate both data services at the same time. And definitely switch off cell data when another WLAN AP is found and activated.
So not a feature but a bug.


edit: found another good read (occurence?) from over 6 years! ago:
see fourth comment

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I have never seen anything like it over my years of using SFOS, if anything it will stick to unusable WiFi networks.

attah ( 2020-04-12 14:23:14 +0300 )edit

And I have never ever seen a pink elephant ;)

No serious, I also found out by accident only.

And another bug I have run into for the first and only time just three weeks ago is the well known connman bug loosing all WLAN availability when connecting to open WiFis on e.g. an airport.

peterleinchen ( 2020-04-12 16:09:55 +0300 )edit

Since 3.3 (EA) I don't see this problem anymore

Blizzz ( 2020-04-12 16:46:33 +0300 )edit

Is it not a bit early to say so? :)

But thanks for reporting back.
So together with @MystIsland 's comment we are already three people reporting / suffering from this.

I'd like some @jolla statement if already known?

peterleinchen ( 2020-04-12 20:27:59 +0300 )edit

Well, I had the same issue before 3.3 and after upgrading to 3.3 i can no longer reproduce it.

Blizzz ( 2020-04-13 01:54:36 +0300 )edit