Use nagstamon with icinga
nagstamon supports the old icinga web interface.
To configure that:
htpasswd -c /etc/icinga/htpasswd.users icingaadmin #enter password for root user cat /etc/httpd/conf.d/icinga.conf # note the virtual paths to the root (likely ./icinga) and cgi-bin (likely ./icinga/cgi-bin)
Use these two paths to configure the nagstamon connection.
Consider the authorized* entries in /etc/icinga/cgi.cfg
On Windows, the nagstamon client config is stored in: %userprofile%\.nagstamon