Command-line tools

Command-line tools are used each day by security professionals, therefore, for the Security + exam, you must be familiar with these, and so I have provided a screenshot for many of these. We are going to see when we would use each of these in turn:

  • Internet Control Message Protocol (ICMP): ICMP brings back the replies when you use command-line tools, therefore, if you block incoming ICMP on the network firewall, none of the tools will work externally.
  • Ping: Ping is used to test connectivity to another host. In the following diagram, you can see that we have pinged the hostname,, and we have received four replies. The Total Time to Live (TTL) is a maximum of 128 seconds; in this case, it is 47 seconds—see ...

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