1)Searching with Grep
One of the simplest ways to analyze logs is by performing plain text searches using grep. grep is a command line tool that can search for matching text in a file, or in output from other commands. It’s included by default in most Linux distributions and is also available for Windows and Mac.
To perform a simple search, enter your search string followed by the file you want to search. Here, we search the authentication log for lines containing “user hoover”.