In this ONLAMP article, Æleen Frisch, author of Essential System Administration, ranked Cfengine #1 in her Top Five Open Source Packages for System Administrators. The article illustrates parts of what can be done with Cfengine.

You may very well incorporate your custom shell or perl scripts with Cfengine, but as for basic task such as maintaining file permissions, monitor disk usage etc, go for the in-built functionality.

I highly recommend Cfengine to any *nix system administrator.

Andreas
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