A network error is reported when the scanner attempted to connect to the Qualys Cloud Platform and it failed. Important - The scanner is not functional until the error is resolved. Make sure the network set up and/or proxy configuration is correctly defined in the scanner appliance console.
You’ll see a COMMUNICATION FAILURE message if there is a network communications breakdown between the Scanner Appliance and the Qualys Cloud Platform.
The communication failure may be due to one of these reasons: the network cable was unplugged from the Scanner Appliance, the local network goes down, or any of the network devices between the Scanner Appliance and the Qualys Cloud Platform goes down.
If there are no scans running on the Appliance - The next time the Appliance sends a polling request to the Qualys Cloud Platform, the polling request fails, and then the COMMUNICATION FAILURE message appears.
If there are scans running on the Appliance - The COMMUNICATION FAILURE message appears after the running scans time out. Usually the S1 LED turns off after the scans time out. If this message appears, it is recommended that you use the Qualys user interface to cancel any running scans and restart them to ensure that results are accurate.
After the root cause is resolved, you'll see the COMMUNICATION FAILURE message until the next time the Appliance makes a successful polling request to the Qualys Cloud Platform. Then you'll see the Appliance's IP address - friendly name and you can start scanning using your Appliance.
Note - The COMMUNICATION FAILURE message may not disappear right away. There may be a lag time after the network is restored and before the Appliance is back online, depending on when the next polling request is scheduled. Additional time is necessary for communications to be processed by a Proxy server if the Appliance has a Proxy configuration.