Armbian X96+ HDD USB issue

[michal890203]

Hi,

 

I have X96+ with armian. I have issue with usb hdd (usb 3.0) on both usb ports (2.0/3.0).Disk have ext4 partition. During hisk work very often disk unmounting (i hear when thisk stoping). In effect the disk is mounted as read-only and of course it generates disk errors that are repairable with fsck.

 

What could be the reason? A badly mounted drive or a sluggish, dying power supply? How I can diagnose this? Any ideas?

 

I simply mounting disk in fstab

 

LABEL=usb-hdd   /media/usb-hdd  ext4            defaults,rw                                0 0

 

[SteeMan]

Is the USB drive externally powered?  I wouldn't expect a cheap tv box to supply enough power over USB to be stable.

[michal890203]

Thanks for reply.

 

No, it's dont have external power supply. I asume box require max 1A and for USB 2.0 / 3.0 max is 0.5A / 0.9A. It shouldn't by trobule speical he came with 2A power supply. I assume frequently work on maximum power caused some damage.

I decided test other power supply, beacuse it's was works fine on begining. So I bought some AC adapter V5 4A. I aware of power reserves, it was intencional in the hope that it will withstand 2A without any problems for long time.

 

Now I doing stress test and after ~200gb read it's look to be fine now.

 

Btw. I not expecting much from this cheap tv box. It was missed purchase as TV Box, unused, so I thought I make linux server form him for media. If it turns out after some time that the problem still occurs, I will simply throw it away and I will go in some other solution.

[jock]

USB ports are just not able to deliver such amount of power a disk drive requires.

USB 2.0 specifications rate the current that may flow through an USB port is at most 0.5A, USB 3.0 should be raised up to 0.9A.

 

Nonetheless, tv boxes usually have a much lower power rating for such ports just to drive "simple" and lightweight peripherals like usb sticks or wifi dongles.

Notebook HDD drives require much more current than 0.5A during spin-up, so often they can't even start rotating. Stressing the circuitry with too much current requirement also leads to voltage drop, so instead of 5V you will probably see less than 4.5V over the line, which is by far outside specs. That causes the spin-down issue.

 

I really doubt you got a real 5V 4A power supply: such a PSU should have very thick cables and be quite heavy. Even if your PSU is really capable of delivering 4A, everything in the middle from the PSU to the hard drive should be capable of sustaining such current (ie: there should be a negligible resistance in the path, due to Ohm's law), and this is just not true because traces in the tvbox are tiny and there are current limiting chips to avoid such high currents passing around on purpose.

[michal890203]

After 1,5 week of use new AC adapter I can confirm it was the issue.

 

@jock I aware it can't have this 4A, but mayby have. What I bought it's not regular AC adapter but so dedicated for leds (ATS024T-A050) it's little bigger, so mayby it's fulfills the manufacturer's promises :P... it's doesn't matter, it's have to give only 2A and not get faulty after near time . And it cost less than 10$ so it was worth to try  

 

Thanks all for awsers