Question Why is raid over usb bad?

[vq12]

I have a 4 bay enclosure attached via usb to a raspberry pi. I have 2 drives in raid 1, handled by mdadm on the pi.

I was going to add 2 new drives in a second raid1 but I found out that it is not advised to do raid over usb. Why is this?

So if I switch my enclosure from usb to sata and use a sata hat on the raspberry pi then I should be okay?

Thanks

 

[USAFRet]

First off, why a RAID 1? Much less 2x RAID 1 arrays?

Over USB? Any burp in the USB connection may cause the array to fail.

 

[vq12]

First off, why a RAID 1? Much less 2x RAID 1 arrays?

Over USB? Any burp in the USB connection may cause the array to fail.

Raid 1 because I need redundancy. 2x because first raid was a small test, 250gb next raid would be 12tb.

Why are there burps over usb but not sata? If I switch to single sata on enclosure and add a sata hat to pi will my raid be less failure-prone?

Thanks

 

[USAFRet]

"redundancy"
You do realize that is not "data protection", right? That is only for physical drive fail. It does nothing for all the other forms of data loss.

USB? All depends on how it is connected. 2 drives in one enclosure? Much less potential problem than 2 drives via 2 different USB connections.

 

[vq12]

"redundancy"
You do realize that is not "data protection", right? That is only for physical drive fail. It does nothing for all the other forms of data loss.

USB? All depends on how it is connected. 2 drives in one enclosure? Much less potential problem than 2 drives via 2 different USB connections.

I understand the risks with raid 1.

My setup is a 4 bay enclosure connected via a single usb. After some additional research I do wonder if I would have been better off with an enclosure that uses individual sata per drive...

So at this point I'm trying to decide my best course of action- use enclosure as is, with usb. Or switch to sata or if I need to rethink my plan all together

Thanks