Pro and Con: The case for Scripting

Scripting rules. Of course you should be in favour of scripting; it has the power to free you from an unbelievable amount of drudgery and tedium.

It's true that scripting is also undeniably powerful and so potentially very dangerous, but this just means it has to be controlled.

Scripting gives you the power to automate any task. To be able to write a script you basically need to learn how to program - and this is true no matter what enthusiasts and introductory books might tell you in an effort to get you started.

Scripting is real programming and as such simply acquiring the skill is a mind altering experience and so worth doing. If you can program you have demonstrated your ability to think clearly, precisely, and some would say logically.

Not everyone seems to have the necessary brain wiring for the job; so don’t be too disheartened if you find it difficult, perhaps even too difficult. It is an exclusive club.

Once you know how to construct a script you can start reaping the benefits. If there is a job you do on a regular basis, or a task that you have always thought would simply take too long, then these are potential targets for a script.

You can write a one-off script to make a network-wide change and simply throw the script away when you are finished. Such one-off scripts are not usually discussed or considered when evaluating the usefulness of scripting in general. Most of the criticisms of a scripting approach to network management point out that scripts tend to be under-documented, under-developed and not transferable to other users. However, given that the vast majority of scripts are private to the person who created them, these issues don’t really apply.

If, on the other hand, you feel the temptation to make your script available to a wider audience then you need to consider all of the principles of good software design and development which is a very different undertaking. The usual rule is that you shouldn't try to use scripting to solve other people's problems unless they are extremely simple or extremely transient.

Core day-to-day network monitoring and management needs to be implanted as part of the permanent and professional infrastructure - not as a script that you cooked up in a few minutes.

Of course, even personal ad-hoc scripts can be a problem. That script that you wrote to delete a few rogue files could just delete everything on the hard disk if you get it wrong! However, this is just the continuation of the responsibility not to do anything damaging to the system that all administrators have. For example, you can delete large chunks of data with a single click or SQL command - but you just have to be careful not to do it.
 
This is perhaps where it is appropriate to point out that scripters haven't been particularly well served in terms of tools to make scripting easy and safe. There are few development environments for scripts that make the task as easy as developing a C# program in Visual Studio, say, and there are even fewer facilities that make it possible to adequately test a script in a controlled environment before letting it loose on the real system.

Equally, the quality of documentation is poor especially when you consider the ancillary technologies such as WMI or any of the operating system APIs that make scripts so powerful. Again these are the conditions a scripter has to simply live with but they do make the task far more difficult than it needs to be - and this is regrettable.

So is scripting evil? Not if it is used in the right way:

Learn to script - it’s a good education and great for the brain, so much better than a crossword or a sudoku.

Don't write scripts for other people to use or to be incorporated in any way to the permanent infrastructure of the system.

Always regard scripts as disposable. If you do find a script that elevates itself to being indispensable then get it converted into a professionally finished utility complete with documentation.

Treat any new script with care and suspicion - it could be just about to bring the system down with a single bound…. (but then you could do that anyway without a script).

If you follow these simple guidelines and don't become overly ambitious or precious about scripting then it will all work in your favour.

Read the case against scripting: scripts are just too powerful and too uncontrolled, and human beings are too inventive