The status is determined by comparing the previous two scans, whether these are initiated manually through the web interface or if they are triggered as part of a scheduled scan operation. The test looks for differences in Host results as well as the Port / Service results.
Status OK: This indicates the previous two scans are identical. Status Changed: This indicates there is a difference in results of the previous two scans. Status No Data: There is not enough data to determine the status (there are not two results available for comparison). Status Running: Currently a scan is running, refresh the page to check the results. Status Error: This indicates a problem with the most recent scan.
Are your results “0 hosts UP”?
If you are testing open ports daily or weekly and find Nmap is returning 0 hosts up. There are a few possibilities. If your external facing system is not responding to Ping from external sources then the IP Address will not be scanned. Nmap first attempts to discover if your system is UP by sending an ICMP ping; so in the event that your border firewall or router is dropping ICMP packets the scanning will not continue as your systems will be classed as being down.
A second thing to check is that you have specified the correct protocol (IPv4 or IPv6) depending on your system. A system wrongly classified will be reported as being down, as the Nmap scanning engine will not receive a Ping response from the invalid IP Address.
Intrusion Prevention Systems are also a possible cause of the lack of response, if you are using a system with a IPS in place. The IPS may detect the scan and block packets from our IP Address. Check your IPS for alerts or if you are a hosted customer check with your service provider to see if they have any IPS blocking mechanisms in place.
This is a new tool providing access to a daily monitoring service based on a scheduled port scan.
Access to this feature is restricted to Silver level Members.