This is “Welcome to Zabbix” screen. When installed, use user name Admin with password zabbix to connect as Zabbix superuser.
When logged in, you will see “Connected as Admin” in the lower right corner of the page and access to Configuration and Administration areas will be granted:
In case of five consecutive failed login attempts, Zabbix interface will pause for 30 seconds in order to prevent brute force and dictionary attacks.
IP address of a failed login attempt will be displayed after successful login.