If you have used a CD-ROM, VGA, Serial image without a config import you are by default able to (a) log into the root shell using the user “root” with password “opnsense”, or (b) log into the installer using the user “installer” with password “opnsense”. The GUI will listen on https://192.168.1.1/ for user “root” with password “opnsense”. Using SSH, the “root” and “installer” users are available as well on IP 192.168.1.1. Note that these install medias are read-only, which means your current live configuration will be lost after reboot.
Welcome! Both `root' and `installer' users are available for systemsetup or invoking the installer, respectively. The predefined rootpassword works for both accounts.