Apache Bus error (7) during upgrade process from 8.0.3 to 9.0.0

hey Georgi

my Integros teammates have warned that such an issue should be a subject of investigation.
However, they gave a few ideas from their experience that probably could be of help: 
- there could be smth left uncleared in the environment - check whether the cache is deactivated, or old sessions left in Redis 
- there also could be a custom code deprecated in the target Sugar version, some third party library deployed as PHP module

Best,
Dmytro

Hi Dmytro.

Thanks for the insight. I suspect that the Bus Error might have something to do with file read/write operations.

The sugar upgrader seems to write some kind of state into a specific file at quite a rapid rate. Do you have some experience or further insight on this aspect?

Similar Bus Error is quite easy to reproduce with a simple script performing a file_put_contents() if the script is called often enough.

Thank you Dmytro! We did disable all cache. As Viktor pointed out in our case it seems that it has to do with I/O and is likely related to our OS/PHP specific setup. 

I would recommend to try to replicate in a different box with an update OS or instead of Centos try Ubuntu. PHP 7.1 has few bugs, some extension deprecations as well. But is very difficult to give a correct path.

Sorry, guys, teammates have nothing to add without investigating. We've seen similar errors in our practice but they were related to reasons mentioned above

Thank you! We have determined the same -- it seems our environment is out of date / may have compile issues. Good to know others have experienced the same problem though :)

This seems like an issue with the hardware. But you can check elasticsearch too if it is going down or not during the upgrade process.