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Monday, July 28, 2014

Ten Computer System Administration Principles


The Device Boom
With the explosion of tablets, smart phones, apps, fitness monitors, remote controls and personal computers, we have been thrust into being computer system administrators.


Breathe
Making matters worse the tools we use to manage these devices has not kept pace with their population explosion. Some vendors, who will go unnamed, have made matters worse by stripping out features for Home users that ease routine administrative tasks like backing up irreplaceable information, updating operating systems and migrating files. You know - email, photographs, documents, financial records, blog entries, homework and so forth.


A careful reading of these ten administrative principles can lead to new places. They can be combined to make new derived principles. Some are similar, but just different enough to warrant their own mention For others you can substitute the word "house", "car", "pet" or even "relationship" to derive additional benefit.

Principle 1:  The Repair or Replace Decision
After concerted good faith effort to fix a broken "computer", if the "computer" does not respond, then it should be replaced without mercy.

Principle 2: The Cost of Additional Computers
For each additional computer system that you maintain, your time is diluted by the total number of computers. So if you have two computers that you often use, you must spend twice as much time maintaining them. Three computers will require three times as much time to maintain. If you have five airplanes you can spend all your time and money maintaining them and none of your time getting to fly them.

Since time is money, this also pertains to computers you pay someone else to maintain.

This principle gives us one obvious thing and one surprising thing.
The obvious is that we want the fewest possible machines possible, that get the job done.
The surprising thing is that if we already have 10 computers, adding an additional one doesn't cost very much. This leads to server farms and the economies of scale.
But I am assuming you don't want to run your own server farm. This leads us to ...

Principle 3: The Cloud Advantage
It is more economical to use a computer in the Cloud, provided it is secure, than it is to maintain your own server. Every second your own server runs, the more of your time and money it saps as it becomes obsolete. I use Dropbox (DB) for this purpose. I can access everything I do from ANY computer ANYWHERE I am located. The first 5 GB is free and they charge after that. DB runs the server farm. DB does the backups. DB fixes the broken equipment. DB is the transparent utility.

Principle 4: The Dual Platform, Dual Browser Safety Net
After losing support on various platforms through the years I have learned:
Any software you buy or use should run efficiently on more than one platform, currently chosen from the set {PC, Mac, Linux}. Any web-borne software you buy or use should run in more than one browser, currently chosen from the set {Chrome, Firefox, Safari, IE}. The food chain alphas flip every decade or so, no matter who was on top to start with.

Principle 5: Legacy Code: If you have legacy code you have to keep the legacy computer running in both hardware and software. The same thing applies to code that is not dual platform or dual browser.

Principle 6: Redundant Systems: When running an important system, it is valuable to have an IDENTICAL hot backup waiting in the wings in case the primary system fails. Note that this principle balances the cost of additional computer principles like porridge and the three bears. By which I mean, 1 critical system is too few, 3 is too many, and 2 is usually just right. In fault-tolerant systems that have "votes", you want odd numbers of machines so you can take the best 2 of 3, the best 3 of 5 and so forth. This gets into RAID disk arrays and error-correcting memory schemes, so that fault tolerance can live at the subsystem level, at the box level, or both.

Principle 7: Backups and Archives:
Always have at least one and preferably two copies of any document in addition to the original. The copies should be on a different physical drive, and preferably in a different physical location. This can get unwieldy, see principles 1, 2 and 3 for guidance.
If you backup a file that has a virus, the virus will be in the backup.

Principle 8: Monetizing Content:
Any content, software, or data, that you are "spinning" on an available drive should produce value for someone. If it is never accessed or used, there is no use paying to spin it. It should move to archival storage which is a HUGE but separate issue.

Principle 9: High Value vs. Low Value Content:
If you have authored specific content, that content is of high value. If you did not author that content and someone else is spinning it, then you don't have to. Its value is lower because it is reachable elsewhere. If there is high demand for the content then you need a redundant system or mirror.

Principle 10: Make vs. Buy Decision:
Don't make something when you can buy that thing for less money and time than it would cost you to make it. You should also consider the cost of the environmental impact of the life cycle of the thing when tally your cost.


(Disclaimer: this content is offered without warranty of merchantability or fitness for any purpose, expressed or implied, which really should have been its own principle!)