Raspberry Pi where hassio runs from external disk


#1

As many are facing issues with sd card limitation on read/write cycles it would be nice to have it running on external ssd drive.

First I do not know what are the limitations using this approach (e.g. speed …).

I would immagine an image to put on the sd card in order to make it booting from the external drive, where we would place the hassio stuff…

What do you think ?


#2

I think it’s needed.

The whole OS doesn’t have to move to a USB SSD, just the database that gets the majority of disk write activity.

The USB ports and Ethernet port share the same controller, so speed is never going to be as good as 480Mb/s (I’ve read 220Mb/s is about tops for USB and 90Mb/s for Ethernet) but this is about reliability not speed (which will still be better than microSD card read rates).


#3

In the following article, scroll down to the “microSD” section:
https://www.jeffgeerling.com/blog/2018/raspberry-pi-3-b-review-and-performance-comparison

Even with a high-end micro SD card, don’t expect better that ~20 Mbps writes. Fortunately, for garden-variety home-automation purposes (intermittently writing logs), that’s adequate.

The principal advantage of using an SSD (as opposed to an SD or USB thumb-drive) is superior longevity. However, don’t expect them to be a miracle cure for all illnesses. If the RPi’s power supply is marginal or power is interrupted during disk-writes, the SSD won’t magically fix these errors.

Don’t bother buying a high-performance SSD for the RPi; you won’t experience the extra performance. A low-end SSD is capable of operating faster than what the shared USB 2.0 bus can sustain.


#4

I have used USB flash drives and run a virtual HA from it, no SD card, on RPi3B+, from this it looks like ssd is possible as well: https://www.raspberrypi.org/forums/viewtopic.php?p=1385818
Have not tried this myself.