We have nginx running, and for reasons I don’t understand, it seems to
be caching content to /var/lib/nginx/proxy. I can’t even find this
setting in the configuration anywhere, i.e. the following returns
nothing:
I would rather suggest it’s proxy temporary files, not cache. If
you don’t want nginx to buffer responses to disk, use
proxy_max_temp_file_size directive. See here for details: