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We recommend that you turn off SELinux. Permissive mode was tested and it worked well, just very nagging; the default mode is known to interfere with NMIS. Disabling SELinux is a lot easier than performing the extensive configuration that SELinux needs. To check if SELinux is disabled you can use the command getenforce. If SELinux is enabled in CentOS 6.8, an example of how to disable it is below:
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The installer does require Internet access for installing pre-requisites using apt-get, yum and CPAN (but we do have a few suggestions for dealing with a system where Internet access is restricted).
As of 8.5.6G using the installer is the only supported method for installing or upgrading NMIS, because by now it is now suitably mature and robust, and because it's very very easy to miss crucial operations in a totally manual installation. Please see the Advanced Installer Use section at the bottom if you need more precise control over the installer.
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Check the NMIS Dashboard. If the web server is running but you can't access the GUI check your firewall; some Linux distributions do ship with a firewall enabled by default (e.g. RedHat 7) so a quick sudo iptables -n -L is recommended to verify the firewall status.
After authenting authenticating you should see the dashboard in all its glory, likely overlapped by the "Basic Setup" helper panel if this is an NMIS installation from scratch.
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