but on on server i am getting the following error
attachments/do-upload.json" failed (2: No such file or directory),
"POST /xxxxx/attachments/do-upload.json?hash=5e0fb3c3de561e578d1e2ad01e92e289&content_type=post HTTP/1.1"
This is from Nginx error log:
2016/04/07 11:30:24 [error] 22142#0: *4354 open() "/var/www/html/overlandsphere/overland-forum/attachments/do-upload.json" failed (2: No such file or directory), client: 22.214.171.124, server: overlandsphere.com, request: "POST /overland-forum/attachments/do-upload.json?hash=5e0fb3c3de561e578d1e2ad01e92e289&content_type=post HTTP/1.1", host: "overlandsphere.com"
Is that error appearing every time, no matter the file?
That would seem to by implying that it's failing to open the connection to (presumably) your PHP-FPM server, which I presume you are connecting to using a socket. The "no such file or directory" message would likely be referring to the socket file.
If so, that's very bizarre and I have no idea why that would trigger for the Flash uploader. The error would be happening internal to Nginx, as PHP isn't even started then.
It seems like that might imply that some rule is causing that URL to hit a different location block, since Nginx only triggers one per request. As a related example, I just noticed your RSS feeds don't work because this rule:
I'm not seeing an obvious rule doing that in the zip you provided (which I only just noticed now), though I'm not sure if there are other config files being included (perhaps your local nginx.conf file, mentioned in default.conf).