Problems connecting to mobile data on Sony Xperia XA2 with UK Plusnet Mobile

Problem

Bought second hand XA2, installed SFOS 4.0.1.48, got a new SIM from provider, adjusted APN settings, I always get this in the logs while it re-tries to connect to a mobile network:

connmand[4563]: Skipping disconnect of /ril_0, network is connecting.
ofonod[2973]: Activating context: 1
ofonod[2973]: Unexpected data call status 28
connmand[4563]: [ofono] ERROR! GDBus.Error:org.ofono.Error.Failed: Operation failed

Tried vendor images v16 and v17 with the same result. A different SIM card (UK 3) works, but I have no data plan so I could only test their website - still counts as “mobile data”.
The device should be unlocked, and I am assuming that I wouldn’t be able to make/receive calls/texts with the Plusnet SIM as I am currently doing.

Before installing SFOS, I did test this and was working with Android.

Resolution

  1. I downgraded to Android using Emma (https://jolla.zendesk.com/hc/en-us/articles/115004283713-Reverting-Xperia-device-to-Android-OS-and-reinstalling-Sailfish-OS)
  2. Tested that the mobile data connection worked, and indeed it did - took note of APN/MMS settings from Android (not surprisingly, the APN settings matched what the operator provides in their website, but not the MMS ones)
  3. Upgraded back to SFOS, observed how the problem was reproduced, configured APN/MMS
  4. Finally connected to mobile data successfully, albeit only in 3G
  5. Flight mode on+off+reboot and the phone is now on 4G and mobile data works (hopefully it stays this way)

Plusnet UK APN/MMS configuration

This configuration worked for me as of time of writing and is slightly different to what Plusnet UK claims it ought to be. Use at your own risk.

Data access point

Connection name: EE Internet
Access point name: everywhere
Authentication: PAP or CHAP
Username: eesecure
Password: secure

MMS access point

Connection name: EE MMS
Access point name: eezone
Protocol: IP
Authentication: PAP or CHAP
username: eesecure
Password: secure
Proxy address: 149.254.201.135
Proxy port: 8080
MMS message centre address: http://mms/

Before anybody starts freaking out about seeing usernames and passwords “on the internet”, this information is already publicly available and to be honest I have no idea why they even bother to implement authentication if you can only connect to their network when you have a SIM card and give them money. Education on this point is welcome :wink: