I have a problem, as I think, with my prosody configuration: When I am sending files (for example photos) bigger than ~2 or 3 megabytes (as I established experimentally) using Converstions 2.* version (android IM app) it transfers these files using peer to peer connection instead of uploading this file to server and sending a link to my interlocutor. Small files are transferred well using http upload. And I couldn't find a reason for such behavior. Here are some lines for http_upload module from my config, that I took from official documentation (where I hadn't found a setup for turning off peer to peer files transfer):
http_upload_file_size_limit = 536870912 -- 512 MB in bytes
http_upload_expire_after = 604800 -- 60 * 60 * 24 * 7
http_upload_quota = 10737418240 -- 10 GB
http_upload_path = "/var/lib/prosody"
And this is my full config: https://pastebin.com/V6DNYrhe
