hi guys i’m using a raspberry pi2 with a 3a power adapter. I had one external hdd hooked to the pi and running fine, yesterday i decided to have a second external hdd and i kept having the input/output error on the first one when downloading a file to it. I run a quick smart on the disk everything seems fine, i also run chkdsk and no errors where found. so my question is; can the rpi feed to USB hdds or is it something else?
Well it seemed to work fine with the one that was running fine right?
Try the problematic drive with the original hdd disconnected.
Im running another extended test to make sure nothings wrong then ill try with that one hdd alone
it looks like the rpi can’t handle 2 usb hdds, i get I/O errors when theres some moving/copying on the hdds. i’m sure it’s not osmc related.
The pi can’t power two USB drives simultaneously, no - all the USB ports share a common power line so what is used by one isn’t availsble on the others. If you need two drives you’ll need to connect them via an externally powered hub.
That’s what i figured 
not very convenient as it clutters the set up a bit. Can the pi 3 do the job or is it all the same?
I wouldn’t bet on it.
You’ll always need either a powered USB hub or the type of portable HDD that has it’s own powersource if you want to connect more that one. With the early RPis you always needed external power.
Once i removed the second HDD everything worked fine, so it seems that u need to have a self powered USB hdd because the pi can’t power a lot of usb peripherals