I recently (re-)installed SFOS to an Xperia XA2 Ultra (H3213). No problems, everything seems to be working fine so far.
However… both Olf’s excellent guide and SFOS docs recommend upgrading to Android 9, which appears to correspond to baseband version 50.2.A.xxx, but I cannot find any justification for that.
Mine is still on 50.1.xxx.
Should I expect problems down the line? What are people’s experiences? What’s the reason Android 9 is recommended over 8?
The reason / justification for this is in the guide, but not explicit written:
Do not blindy upgrade Android!
Otherwise you may not be able to install SailfishOS or it might not run properly.Background: Because firmware blobs may become updated by Sony’s Android updates and these blobs cannot be updated through SailfishOS (yet?), it makes sense to update your Xperia to the last release of Sony’s Android, which is supported by SailfishOS, before flashing SailfishOS (Reference).
I am aware that “firmware blobs may become updated”.
I am asking for specifics, maybe also anecdotal evidence. Things that work better on SFOS with 50.2.A, compared to 50.1.A.
Are you pointing to anything particular in that chat log? It seems to repeat the same unspecific “we don’t know what Sony/Android may have put in their last update, so better use the newest that is known to work with SFOS”. I’m looking for reasoning that goes beyond that. Because nowhere does it say that SFOS will fail with the older Baseband version underneath. Both are listed as valid options afaics.
I guess in the end I’m asking if anybody has actually experienced anything that would justify the upgrade of Android & subsequent reinstall of SFOS. Or conversely, if people have been running SFOS based on the older Baseband without problems.
Why don’t you simply create an image of rootfs and home e.g. using dd (on the XA2 Ultra it’s the mmcblk0p76 partition to make an image of) and then simply restore it and this way get back your SFOS system in exactly the same state you imaged it, without actually any hassle other than waiting some 20 minutes or so for dd to do its job. Heck, with the XA2U you can even restore the image using fastboot from PC…
This way you can actually safely test multiple Android versions and always be able to go back to your imaged system. No need to reinstall it from scratch.
P.S. On the XA2 Ultra I recall once having SFOS installed on top of LineageOS 18 (i.e. Android 11), and it still worked just fine.
There are now also Sony binaries for the XA2U up to Android 11, so maybe they’re worth testing, too (which actually carries no risk as they can be reflashed back and forth anytime).
I asked this question 9 months ago, and have not experienced any problems since then.
Thanks to olf and wetab for adding info.
Oh, thank you @ohnonot for reporting, I was looking exactly for this kind of info.
Years ago my XA2 was flashed over android 8 (not even 8.1!) and then updated all the way to SF 4.2.
Now it’s about time to re-flash the latest version of SF on it, but without reverting to Android, i.e. staying on 8.0 baseband (with my skills, the least I do, the better).
Have you already updated to 4.6? Any problems with that?
Sorry for the late reply. On 4.6. Everything is still working OK.
No worries, actually your first reports were enough to encourage me and went in to re-flash over Android 8.
Have been testing as main device for just about ten days (some intense ones, with traveling).
So here’s my report to add to the statistics of your thread:
XA2 flashed with SFOS 4.6 over android 8.0 with Sony binaries v16.
No Android App Support installed - for now.
So far so good.
Everything works as you would expect from the OS and the stock apps (connectivity, location, internet sharing and so on).
Navigation (Pure Maps) works fine using using device only mode for location and it always founds me in a couple of min or so).
Small issues with the browser crashing often, but I won’t blame the android layer as this is a known issue.
As for connectivity I have to note that it takes a bit longer than before to find the network when exiting offline mode and that while traveling I did not have a working mobile internet connection on some Croatian networks - but I was still able to manually switch to different ones and restore it, so, just peanuts.
Previously I had never had a problem with roaming, yet I had never been in those places before. And again I am comparing two different SFOS version over the same android layer, for proper testing I should revert to android 9, re-flash 4.6 and go back on holiday. Yay!
Overall it all feels smooth: a big thanks to Jolla for supporting so well my beloved 6 y.o. old, rusty phone.
“Revert”?
AFAIU you never had Android 9 “(not even 8.1!)” installed on your Xperia XA2, right?
So your “test” “compares” Android 8 firmwares (v50.1.A.xx) with itself, as you did not change it, AFAIU.
You are right. The correct sentence should have been “revert to android, update to 9 and…”
More than a ‘test’ a real life scenario with my main device where I am reporting how things went with SFOS 4.6 over android 8.
As I never had android 9 installed, I cannot know if any issue was due to operators problems or the old android layer. So I share the info as it is.
But I stress that was an issue that showed up with one network only (HR 01) and (for what it’s worth) my IMPRESSION is that it was not an android layer problem, as everything else (including connectivity anywhere else I travelled) has been working perfectly.