This depth of knowledge pays off because you can't point and click for every Linux server function. You can keep your CLI time to a minimum by utilizing Web-based administrative tools like WebMin (webmin.com), but even if you use user-interface-friendly distributors like those from Red Hat or SuSE, you'll still have to roll up your sleeves and delve into a terminal window occasionally.
Knowing the CLI also makes automation easier. If you're command line-proficient, you simply type in the command line, see if it works interactively and then type that same command line into the scheduler so it executes at a given time. GUI users, meanwhile, have to worry about whether their GUI application supports batch or scheduled processes.
Microsoft is now actively promoting scripting to its MCSEs (Microsoft Certified Systems Engineer), but don't look for that to make CLIs more attractive to MCSEs anytime soon. If you're a Windows administrator who's comfortable with command-line utilities like LINKD.EXE and NETSH, and could navigate .INI files in the glory days of Windows 9x, you'll do just fine with Linux.
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