How can you run Nmap to scan the most common 100 ports across a list of hosts provided in a file, and save all outputs?

How can you run Nmap to scan the most common 100 ports across a list of hosts provided in a file, and save all outputs?

• A. Nmap -iL targets.txt -top-ports 100 -oN results
• B. Nmap --top-ports 100 -iL targets.txt -oA results
• C. Nmap -iL targets.txt -top-ports 100 -oA results
• D. Nmap --ports 1-100 -iL targets.txt -oX results

Answer: (B)

The key idea is using Nmap’s top-ports feature together with a file of targets and a broad set of outputs. By specifying the top-ports option with 100, Nmap focuses on the 100 ports it considers most commonly used, which often yields the most useful information quickly rather than sweeping a fixed numeric range. Reading targets from a file is done with the input-from-file flag, which tells Nmap to take each host listed in that file and scan them. Saving all outputs is best done with the output-all flag, which writes normal, XML, and grepable formats under a common basename so you have multiple formats for reporting and later parsing. So this combination is ideal: it targets the most relevant ports across all hosts in your list and archives every output type for easy review and automation. Using a numeric range like 1-100 would miss some widely used ports beyond 100, and using output options that write only one format would limit how you can share or parse the results.

The key idea is using Nmap’s top-ports feature together with a file of targets and a broad set of outputs. By specifying the top-ports option with 100, Nmap focuses on the 100 ports it considers most commonly used, which often yields the most useful information quickly rather than sweeping a fixed numeric range. Reading targets from a file is done with the input-from-file flag, which tells Nmap to take each host listed in that file and scan them. Saving all outputs is best done with the output-all flag, which writes normal, XML, and grepable formats under a common basename so you have multiple formats for reporting and later parsing.

So this combination is ideal: it targets the most relevant ports across all hosts in your list and archives every output type for easy review and automation. Using a numeric range like 1-100 would miss some widely used ports beyond 100, and using output options that write only one format would limit how you can share or parse the results.