nginx error "conflicting server name" ignored

You have another server_name ec2-xx-xx-xxx-xxx.us-west-1.compute.amazonaws.com somewhere in the config.

I assume that you're running a Linux, and you're using gEdit to edit your files. In the /etc/nginx/sites-enabled, it may have left a temp file e.g. default~ (watch the ~).

Depending on your editor, the file could be named .save or something like it. Just run $ ls -lah to see which files are unintended to be there and remove them (Thanks @Tisch for this).

Delete this file, and it will solve your problem.

There should be only one localhost defined, check sites-enabled or nginx.conf.