Problem not detection 2nd HDD

Hi,

I have 2 4TB hdds (same model) powered thought usb and formatted in NTFS and i'm using LibreELEC 9.2.1 (Rpi4),

when I connect one of them (either one) everything works fine, but if i connect the other one it's not detected and sometimes the first one is not detected anymore too.

I saw that in most similar discussions someone usually ask for the output of blkid, mount and dmesg

These are the outputs with 1 hdd connected

blkid http://ix.io/2lwy

mount http://ix.io/2lwz

dmesg http://ix.io/2lwA

(if i connect the other one i basically have the same output but it's sda1 and the label is different)

Thse are the outputs after i rebooted with both disk attached

blkid http://ix.io/2618

mount http://ix.io/2lwD

dmesg http://ix.io/2lwF

I'm not sure if it's relevant but the 2 hdds have different labels, I also run chkdsk on widows to make sure it wasn't some kind of ejection problem.

(I read a few discussions like this one, but i didn't find a solution that works for me)

Any ideas?

Thanks in advance

Quote from Iridium

If they are HDDs (Old style mechanical platter type) then they should have their own power supply. Try powering both HDDs via a powered hub and see if you still have issues.

Quote from Nicolas

Hello!

What Iridium told you. I guess both are 2,5" HD's. Two HD's are maybe to much for the Device in Case of Power draw.

... And Take a Look If the HD's have different names.

Regards

Nicolas

Hey thank you both for the reply, the drives are Matrox M3 4TB, these drives unfortunately don't come with an external power supply.

I don't have a powered hub available right now but it's a good idea, i'll try that, thanks.

Quote from Iridium

I would also look at your RPi4 power supply. If it's an official RPi one then you're good to go. If not, then that could cause issues also.

Runvcgencmd get_throttled If NOT 0x0 then you have another problem

the output is throttled=0x0 so i should be fine, thanks for the advice

Quote from Nicolas

I am using 2 powered Hub's from TP-Link for 4 years now. Had different ones before but they finally last

Regards

Nicolas

I actually found an old powered hub and now the disks are working correctly.
It seems that as you said it was a power draw issue, for some reason I dont see those drives in the sources section and i have to go look for them in the file explorer, but no big deal.

Thank you very