NethServer Version: 7 (1611)
Additionally, using the basic directions to set up a manual proxy is not enough and the proxy never works. Do I need two NICs for this? The documentation is very sparse and, in the case of v7, nonexistent -- http://docs.nethserver.org/projects/nethserver-devel/en/v7/web_proxy.html as seen here.
Steps to replicate:
Install fresh from 1611 ISO.
Select the 'web proxy' checkmark and apply from the list of available software.
Allow to install, and complete.
Set proxy to manual from the web proxy section (bottom of the menu at left), and apply.
Get failure as above from the applications/lightsquid section.
Redirect a browser/OS to use the proxy server and it will not answer the browser.
Nmap reports that the port (3128) is open.