OK, so just to clarify, if I have different users for each pool, and nginx is running under www-data but the pool using the cache is running under something else, then I cannot use “purge”? I suppose that makes sense, because if I chmod everything in /var/run/nginx-cache to +rw for everyone, then purge works, but as soon as the cache builds up, the permissions are just 0600 again, under the “wrong” user.
I can “hard purge” the cache by doing an rm -rf of course, but that seems a bit of a “manual” way to do it.
The /purge/ method also works, as does purging when updating a page.
I noticed in the docs that there’s something called fastcgi_store_access http://nginx.org/en/docs/http/ngx_http_fastcgi_module.html#fastcgi_store_access
However, even though I set it up to
all:rw and restarted, it was still writing the files with 0600 permission and “purge all” still didn’t work. Hmmm… I don’t really want to go back to “one user for all pools”, as that’s a bit insecure.