Tips to improve my build?

[no_connection]

The resulting AC magnetic field (due to platter spinning) could potentially demagnetize the HDD slowly. Not a problem though if you scrub regularly as that re magnetize weak sectors.

Then I have had laptop drives just about sticking together due to internal magnets so it might not be a problem at all. Ok maybe not sticking together but you could feel the pull.

 

[cyberjock]

The resulting AC magnetic field (due to platter spinning) could potentially demagnetize the HDD slowly. Not a problem though if you scrub regularly as that re magnetize weak sectors.

Then I have had laptop drives just about sticking together due to internal magnets so it might not be a problem at all. Ok maybe not sticking together but you could feel the pull.

That is such a load of crap I'm not even going to dignify this with a response except to say that you are VERY VERY wrong.

 

[no_connection]

So there is no way for a static magnetic field to demagnetize a disk. Good to know. Then I can store my magnet collection next to my NAS.

 

[cyberjock]

No, you said, and I'll quote you...

The resulting AC magnetic field (due to platter spinning) could potentially demagnetize the HDD slowly. Not a problem though if you scrub regularly as that re magnetize weak sectors.

So clearly the fact that the platter is spinning "could potentially demagnetize" your sectors. Uh, what? Guess we'd better make non-spinning platters because the act of spinning the media makes them demagnetize. Who knew?

 

[no_connection]

No, I said that the platters spinning causing an AC field instead of DC which would demagnetize instead of just turning all the bits in one direction. (with strong enough field).

AC magnetic fields destroys magnets instead of just changing them. For example don't put a magnet close to an AC electromagnet. Learned that the hard way. Takes a huge magnetic field to restore it to working order.

 

[cyberjock]

An AC field? There is no such thing as an alternating current field... Now there are magnetic fields that are created from AC power, but the field itself doesn't "alternate" quite the same. The magnetic field is created, destroyed, then created. Some people even call coils in electronic circuits "inductors".

 

[no_connection]

Sorry, AF would have been the appropriate term.
AC current create alternating magnetic field, so that sprung to mind first.
The resulting field do change direction.

Now there are magnetic fields that are created from AC power

AC current, not power if you want to mark words.

Inductor are more of a description of what they do rather than their form.

 

[cyberjock]

AC current, not power if you want to mark words.

Really want to get pedantic? AC Current.. So alternating current current? Really?

Been an electronics tech for 16 years... So I know a thing or two about this junk...

 

[Starpulkka]

As this has become ridiculous offtopic from a simple you should know that this can happen to your hdds.

Electricity ja magnetism 101 who is intrested learning how physics affects in reallife in your harddrive magnetic recording.
Im sure this dude can teach physics even an anableps and the anableps will love it. Its in enlgish so im sure many will understand what he tells.
Funny how aluminium plate did have zero, zip, none, nothing effect on magneticfields as he demonstrated it. But heres someone that claims hdd aluminium case shields from magnetic fields..

View: http://www.youtube.com/watch?v=qqkUeQ0nsF8

 

[cyberjock]

You do realize the hard drive is an aluminum alloy? That alloy does some very useful things. But keep talking. Remember, I had a magnetometer so I actually got to see firsthand how some of this stuff works. I don't need to necessarily know all the theory to know that it works a certain way. Just like you don't need a PhD in computing to know how to build and use computers.

And hate to break it to you, but I'm not watching a video on the topic when I've already done the experiments for myself. You'd have a new appreciation for hard drive technology when you have to do magnetic testing on hard drives(both magnetic fields created from hard drives and their parts as well as magnetic fields from external items and their influence on the hard drive).

 

[Starpulkka]

Well looks like we both have own experienses, im currently trying to reproduce what happened to my scenario, so far no being able to have checksum errors, funny huh =P (could it be that something else have happened when fan was removed further away, i am open to ideas what have happened) (i do know that same have happened somebody else too, but why it has happened is not clear)
Fan vibration, not believe that, write/reading head thrown off by magnetfield no its so tiny and moves fast dont think so, heat not that too fan clearly kept hdd cool, memory no ecc mem had both cases, only what i can came up is that strong magnet because its a really really thin layer where data is stored on the platter.
Really i am open for ideas what it might have happened, this bothers me. (Yes i do know that case is aluminium alloy mixture and i know that aluminium dont do nothing on magneticfield, just tryed myself on opened case magnet did grab a nail just fine thought, as that dude in video demonstrated, also know that voicecoil magnets are 2 so field is really small) But if you dont have suggestions what have happened then next thing would this be good idea to give on mythbusters =) Still believe that magnet does superparamagnetic effect on platter. Not sure was those hdd models system area on edge of platter, if that happened it would mess hdd pretty good.
Please do tell those aluminium useful things of yours what it does than keeps body strong and spreads heat and reduces resonations.

Finally found what looked for i was lookin in wrong place, smartctl tells whats going on hdd before zfs kicks in data integrity.
(So looks like that smart tests are really really important to do if you want to know hows your hdd doing.)

 

[Tomas Liumparas]

Hello,

I am not sure if this a correct place to post :) But I would also ask some friendly advices regarding my planned build.
I am new to FreeNas, I have some old setup of Nas4Free on which I put all my old HDD's, I am using it for serving movies to my XBMC client, as so far I am happy.

I had a lot of reading based on ZFS and after that I had some more:)

I've decided to build a small system and have some questions based on it:

Hardware:
GYGABYTE GA-F2A85XM-HD3
http://www.gigabyte.com/products/product-page.aspx?pid=4406#sp

ATHLON II X4 740 3.2 GHZ 65W
http://www.newegg.com/Product/Product.aspx?Item=N82E16819113329

2x 8GB RAM
http://www.newegg.com/Product/Product.aspx?Item=N82E16820233218

8x 3TB WD Green Drives

I am planning to build them as this:
RAIDZ1 3+1
RAIDZ1 3+1

I was thinking about building the first RAIDZ, after some time I would add the second one to the same storage pool. Is this build possible? I appreciate any comments made.

 

[DJ9]

Quite honestly, minus the hard drive choice, toss everything and read this.
http://forums.freenas.org/threads/so-you-want-some-hardware-suggestions.12276/

 

[Tomas Liumparas]

Thank you for the comments. Well the first thing why I've choosen this mob, was it's price. 64Gb of maximum RAM and 8 Sata 3 ports. The other components was from mob's support list.

As I can not quite afford an expensive server board, I would try to look some more alternatives. Thank you for the refference, I would continue reading your suggested article.

 

[cyberjock]

@Tomas Liumparas: Don't hijack the thread either. Make your own thread with your own build, but only after you read the stickies on hardware suggestions. If you aren't following those recommendations the feedback you are going to get is going to make you feel like crap because you'll be slapped around a bit. ;)