Hi there,

 

My unraid server started experiencing failures where it will turn itself off (seemingly) without a reason. For example once you try to turn it on, it will shutoff immediately even before reaching POST screen (even before drives start up!). After a few cycles like this, it may turn on and stay on for a few days. But then will turn off at random.

 

There is nothing suspicious in the system log.

 

I have tried running a full memory check (passed) and replaced the mobo (new mobo behaves the same way). Seems that the only component left is ps?

 

Does anyone have suggestions for what I should try?

 

Thanks in advance, jdw

 

In my temporary experimental server, the (cheap and kinda weak) PSU shuts down in similar way when I'm trying to boot with more than 8 HDDs.

 

So my bet would be on PSU asking for retirement. To check, I would buy/borrow/lease/steal an overkill PSU - way more powerful than needed for the server - and try running on it. Make sure PSU has +12V single rail. Alternatively, thoroughly check that every +12 Volts rail feeding HDDs has a headroom for the number of HDDs it is powering.

Second the opinion that it may be the PSU.  Other possible source for flaky and inconsistent crashes is overheating.  If you think that could be an issue you can leave the case open with a fan blowing on it and see how the system responds.

Thanks for the suggestions, I have replaced PSU with 500W version of the one I have - its one of the ones recommended on PSU thread. But it still fails.

 

I only use 4 drives, and power meter says max usage is ~145W.

 

It will fail to turn on (won't even reach POST) several times in a row but then will start, do parity check and after about 24 hours or so of being up will die.

 

 

hmmm, well since you have replaced the MOBO, PSU and tested the RAM, my guess would be that the CPU is overheating and forcing the computer to shutdown before the temps get to hot to cause damage. You may check to see if the CPU fan is working and/or how dusty it is. Also your case might not be getting enough air flow. What temps are your hard drives running at? A good test would be to take off the side panel and stick a big room fan next to it and see if it stays on...

 

A fan like this (LOL this picture is awesome):

Is there any chance it could be the AC cord running frm the mains to the PSU?  I usually keep the same cord even if i change a PSU, just because it's a pain to crawl under the desk and unplug from the power strip.  If you didn't replace that cord you might give it a try.

I had the same thought as Chugiak, and so far the cord appears to be the issue. The server went up on first try and has been up ever since I swapped cords and changed outlets.

 

Thanks everyone for input!

I had the same thought as Chugiak, and so far the cord appears to be the issue. The server went up on first try and has been up ever since I swapped cords and changed outlets.

Wow. That's something I would probably never think of. Thanks for sharing!

I think this is appropriate...

 

I had the same thought as Chugiak, and so far the cord appears to be the issue. The server went up on first try and has been up ever since I swapped cords and changed outlets.

 

Thanks everyone for input!

 

Wow, at least you now have enough spare parts to build a test machine or backup server, lol.