Some common issues if scans doesn’t return any results:
Note: If you have any questions on this topic please start a new thread for each question and link back to this topic so that it can be updated accordingly.
For all installations (GCE/GSM Appliances/VM and Source/Package like e.g. Kali Linux)
The targets are not answering to an ICMP Echo Request -> Check the Alive Test setting of your Target definition and try some of the other available methods. Further reading:
You’re using a custom scan configuration which doesn’t include the following two VTs from the Port scanners family.
Only for own Source/Package installations (e.g. Kali Linux or Debian)
- SELinux is enabled and blocking the scanner from doing its job.
- You don’t have nmap installed or not available within your PATH
Further debugging / logging
The mentioned Nmap (NASL wrapper) and Ping Host VTs allows to configure various settings:
Report about unrechable Hosts configured to yes: include notes if a remote host is considered as dead / not reachable and the reason why.
Log failed nmap calls and Log nmap output configured to yes: Log additional output if nmap was used.
Nmap (NASL wrapper)
- Log nmap output configured to yes: Log additional output if nmap was used.