Is there any configuration validator for linux?

Question

I found something if you mistype some configuration for the Linux. Like set invalid value will cause the System crash.

In my experience. I assign an invalid value for seLinux. The CentOs will not start up. And It is hard to figure out what is it going on. (I nearly want to reinstall the whole system...)

So I wondered if there exists some validator for this kind of configuration. Before you saving the configuration. Basically, It supposed to remind you if there exist the wrong invalid value out there .

Answer 1

It depends on the application, and thus may vary from "ha ha ha, no." to possibly "yes" though given the infinite variety of errors that can be introduced, and the specific needs of the thing being configured, it is more likely that buggy undesirable input will be generated than the error caught by a validator (and then there's syntactically correct but totally invalid configurations such as giving Billy Bob Cletus from shipping a uid of 0 that a validator may have difficulty or no means of detecting). Hence, test systems, staggered roll-outs, code reviews, etc, etc, etc. Otherwise, validation is per application, so for e.g. sudo one would use visudo which has a post-edit verification step (and possibly also first a test system, depending on how critical the change is, how bad the damage would be on screw-up, and how hard a roll-back or recovery would be). Though, again, the completely valid sudoers line of bcletus ALL=(ALL) NOPASSWD: ALL might be really bad news.