This is a placeholder topic for “Raspberry Pi USB 3.0 Hub” comments.
Need more USB ports? This handy accessory turns one USB-A port into four!
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I have been trying to use a Raspberry Pi 4 to host portable HDDs as a shared network drive.
The Pi 4 itself boots from a USB 3 SSD connected directly to the Pi. I want to attach two 1 TB bus-powered portable HDDs for network storage through a powered USB 3 hub.
The powered hub I have been testing appears to destabilise the Pi/root SSD: I have seen I/O errors reading the root filesystem, and at times the Pi has failed to become reachable while the hub is connected. Removing the hub and rebooting restores normal operation.
Would the official Raspberry Pi USB 3.0 Hub, using its external 5 V / 3 A USB-C power input, be suitable for this setup? In particular, can it safely power two portable 2.5-inch HDDs simultaneously while the Pi continues to boot from a separate USB 3 SSD connected directly to the Pi?
Is two HDDs a reasonable load for the hub, and is there any particular limitation I should know about if I later wanted to use more than two bus-powered drives?
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Hi Freya,
The official Raspberry Pi USB 3.0 Hub is a much better fit than an unknown powered hub, particularly if the existing one is back-feeding or suffering voltage drop.
Two typical portable 2.5-inch HDDs should be a reasonable load with a good regulated 5 V / 3 A USB-C supply connected to the hub. However, 3 A is the hub’s total input rating, not a guaranteed 3 A available to the drives—and HDD spin-up current varies considerably. I wouldn’t promise compatibility without checking each drive’s labelled/specification current; simultaneous spin-up is the worst case.
Keeping the boot SSD directly connected to the Pi is sensible. If instability remains, check dmesg for USB resets/I/O errors and run:
vcgencmd get_throttled
For more than two bus-powered HDDs, I’d use drives/enclosures with their own power rather than relying on this hub. All four ports also share the hub’s power budget and USB 3.0 upstream link.
Liam
Thankyou.
I did see in the reviews that someone had gotten the extra power supply for power issues, while doing what I want to do. I have ordered the hub and some other goodies.
I had already decided that if power (or port space) becomes an issue, it is a sign that I need to take it to the next stage .. but I already have so many projects on the backburner, I was hoping this might let me get started … I might not care for a network accessible drive, after all.
I can probably print a housing for the old hub and use it as a charging station, because you can never have too many of those!
