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Can Maintenance Make Data Centers Less Reliable?
miller60 writes "Is preventive maintenance on data center equipment not really that preventive after all? With human error cited as a leading cause of downtime, a vigorous maintenance schedule can actually make a data center less reliable, according to some industry experts.'The most common threat to reliability is excessive maintenance,' said Steve Fairfax of 'science risk' consultant MTechnology. 'We get the perception that lots of testing improves component reliability. It does not.' In some cases, poorly documented maintenance can lead to conflicts with automated systems, he warned. Other speakers at the recent 7x24 Exchange conference urged data center operators to focus on understanding their own facilities, and then evaluating which maintenance programs are essential, including offerings from equipment vendors."
Maybe there's a sweet spot between "no testing at all" and "replacing everything every three months"? In my experience, there is a lot of work to do in most places to make sure that proper testing is done, or at least that emergency procedures are known and people are well trained in them. Very often documentation is lacking and the onsite support staff have no clue where that circuit breaker is. That is the most common scenario in my experience, not overzealous maintenance.
Semantics is the gravity of abstraction
From TFS:
"... poorly documented maintenance can lead to conflicts with automated systems ..."
That doesn't mean maintenance makes datacenters less reliable. It means cluelessness makes datacenters less reliable.
Sheesh.
dragonhawk@iname.microsoft.com
I do not like Microsoft. Remove them from my email address.
There's something to be said for this. Back when Tandem was the gold standard of uptime (they ran 10 years between crashes, and had a plan to get to 50), they reported that about half of failures were maintenance-induced. That's also military experience.
The future of data centers may be "no user serviceable parts inside". The unit of replacement may be the shipping container. When 10% or so of units have failed, the entire container is replaced. Inktomi ran that way at one time.
You need the ability to cut power off of units remotely, very good inlet air filters to prevent dust buildup, and power supplies which meet all UL requirements for not catching fire when they fail. Once you have that, why should a homogeneous cluster ever need to be entered during its life?
Which means for every online server you need an offline test machine -- and a way to simulate the operating environment in order to test. Not many companies have the skill of cash to do that.
vigorous maintenance
excessive maintenance
poorly documented maintenance
Those are all qualified as out of the ordinary. Anything in excess (on either side of the scale, whether it is too much or not enough) is a problem. Of course maintenance must be performed, but I guess some data centers have a strange idea of best practices, or they do not follow them.
Twinstiq, game news
Precisely my thought.
Maintenance, like anything else you do in a datacenter or wherever you work, must be done correctly. If maintenance reduces the reliability of the maintained entity, then per definition, it was not correctly performed.
Doing something correctly requires knowledge, planning and training. Just like everything else.
Although everyone makes mistakes, some people make hundreds of times more errors than others. Whether that's due to inherent lack of ability, poor training, lacking oversight, laziness, time pressures or just a slapdash attitude varies with each person. One place I was involved with (as an external consultant) made over 12,000 changes to their production systems every year. It turned out that well over half of those were backing out earlier changes, correcting mistakes/bugs from earlier "fixes" or other activities (a lot that resulted in downtime, and far too much of it unscheduled or emergency downtime) that should not have happened and could have been prevented.
politicians are like babies' nappies: they should both be changed regularly and for the same reasons
You must not deal with any Oracle database servers. They leak like a sieve.
[John]
Shit better not happen!
Those cars, to be competitive, were engineered to fall apart on the other side of the finish line. Without maintenance they would have failed. They are now engineered to last a few races instead of just one. Odds are they are slightly slower in one form or the other but it being a level playing field, it doesn't matter.