I am having difficulty getting my Varnish/Nginx Wordpress setup working. I had set up varnish to listen on poert 80, and nginx to listen on port 8080, with a rule on wp-admin URLs to pass through to nginx (bypassing the cache). The main blog pages seem to work ok with this setup, but the dashboard and other admin pages are not reachable, which suggests that the varnish configuration is "working" (in that it is behaves differently for the pages with the rule set up). The site itself works fine if I disable Varnish and just set nginx to listen on port 80. I did wonder if there was a problem with port 8080 not being open, so I tried setting nginx to listen on port 8080, and I could not connect.
What I have done to try and diagnose this:
- Set my security group on the EC2 dashboard to allow 8080
- Disabled the Ubuntu firewall
- Tried the suggestions I have seen to get rid of IPTables
- Run nc -l 8080 and tried to connect from another machine. This did not work. Setting nc to listen on port 80 DID work, so it looks like a firewall problem, rather than any nginx/WordPress/Varnish problem.
My question is, how might I diagnose what of the many firewalling services could be stopping the connection (supplemental quation - how do I allow the connection).