Running DietPi on a USB HDD w/o SD

General Discussion
1

Knew that would get your attention.

As you no doubt know the Pi 3 can boot from a USB device with a software modification.

https://www.raspberrypi.org/blog/pi-3-booting-part-i-usb-mass-storage-boot/

I did this and then spent a few hours trying all my USB flash drives - none worked - unless you had a FAT 32 formatted SD card with bootcode.bin on it in the SD slot - but what’s the point of that?

Read in the Pi forum that pink Silicon Power drives worked - the other ones said to work are the more expensive Samsung and Sandisk brands.

Got an 8 GB pink Silicon Power USB 2.0 and then followed this guide:

https://github.com/raspberrypi/documentation/blob/master/hardware/raspberrypi/bootmodes/msd.md

I now have DietPi running from a USB drive and no SD card in the Pi.

An earlier effort with Raspian Lite also worked but apt-get update / upgrade broke it.

Not sure how useful this will be as I don’t think the system is any faster running from USB.

John

2

Hi John,

Knew that would get your attention.

I’ll get you back for that :wink: Just you wait lol

Thanks for sharing your results and info, much appreciated.

We have a request for adding SD > USBHDD feature into DietPi, so i’ll make a note to check your post in detail when we start work on it: https://github.com/Fourdee/DietPi/issues/509

3

Hi Fourdee,

I’m not that impressed with this setup as it is very slow and if you try to edit config files with WinSCP it can time out. This may be a feature of the USB flash drive - a cheap brand that I know are slow - but I’ll investigate further.

root@Pi3:~# hdparm -t /dev/sda

/dev/sda:
Timing buffered disk reads: 10 MB in 38.38 seconds = 266.83 kB/sec
root@Pi3:~# hdparm -t /dev/sda

/dev/sda:
Timing buffered disk reads: 4 MB in 38.42 seconds = 106.60 kB/sec

Yes very slow. No doubt a USB HD (or Sandisk/Samsung flash drive) would be better but I don’t have a spare to try.

John

4

Replaced with a better power supply - and this was the result - much better.

root@Pi3:~# hdparm -t /dev/sda1

/dev/sda1:
Timing buffered disk reads: 48 MB in 3.02 seconds = 15.90 MB/sec
root@Pi3:~# hdparm -t /dev/sda1

/dev/sda1:
Timing buffered disk reads: 66 MB in 3.00 seconds = 21.97 MB/sec

5

Hi John,

30-35MB/s should be achievable with the RPi 3 USB.

I just tried my Sandisk Ultra fit 32GB with EXT4 format. Its taken a hammering, 1year + of DietPi testing and dietpi-backup and restores:

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dietpi-config > tools > benchmarks

Think its about time I got a new one lmao.

6

I got 12.6 with your test well down on the above figures.

7

Got a couple of SanDisk Cruizer Edge 8 GB USB 2.0 drives today (about 1 UK pound each at a store opening) - the Pi3 can boot from these.

Write = 4.4 MB/s | Read = 25.4 MB/s

8

£1?!? I must be shopping in the wrong place or country :wink: lol

9

It was a store opening special offer - 100 only - and they weren’t selling quickly either!

Incidentally given up running the Pi3 by booting off USB as apt-date update/upgrade broke it - and no real advantage over SD.

John

10

hi guys, i’m new to dietpi and try this guide. Everything looks ok, fresh dietpi image boot from external usb ssd drive but startup configuration just broke it. Do you have any sugestion how to resolve this problem?