Matt Penfold
Posts: 9
Joined: Thu Mar 09, 2017 4:18 pm

USB Booting with 2 USB drives

Sun Apr 22, 2018 10:38 am

I am getting my Pi3 to boot Raspbian Stretch OK when I have just one USB drive (an SSD) connected. When I connect a second USB drive it no longer boots, and I think this is because the Pi is trying to boot from the second drive, rather than the SSD.

Is there a way to have two USB drivers attacked and specify what USB drive to boot from?

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HawaiianPi
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Location: Aloha, Oregon USA

Re: USB Booting with 2 USB drives

Sun Apr 22, 2018 11:24 am

Depends on how your system is setup to USB boot. Since you didn't provide any details any answers you get will be pure speculation.

One of my Pi3B systems is booting from a SATA SSD with a USB-SATA adapter, and there is another USB flash drive connected to the system. I've never had any trouble with it. The SSD always boots, even when it's detected last. The system has the OTP USB boot bit set and is booting with no SD card.

If you are using a bootcode.bin only SD card, then that's your problem (bootcode.bin tries to boot the first USB drive it finds, and fails if it's not a boot drive). There is no way to fix that without a new bootcode.bin (modified to address that issue).

If you have the boot partition on an SD card, then you need to edit cmdline.txt and /etc/fstab to use UUID or PARTUUID instead of device names (/dev/sdx). Actually, you may need to do that with cardless boot as well (if those files on your SSD are using device names).

Those are my best guesses.
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RonR
Posts: 2839
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Location: US

Re: USB Booting with 2 USB drives

Sun Apr 22, 2018 6:26 pm

Matt Penfold wrote:
Sun Apr 22, 2018 10:38 am
I am getting my Pi3 to boot Raspbian Stretch OK when I have just one USB drive (an SSD) connected. When I connect a second USB drive it no longer boots, and I think this is because the Pi is trying to boot from the second drive, rather than the SSD.

Is there a way to have two USB drivers attacked and specify what USB drive to boot from?

First, see:
viewtopic.php?f=29&t=196778

Then, edit your /boot/cmdline.txt to contain a line for each bootable device. Comment out (#) all lines except the one you wish to boot (do not have any blank lines):

Code: Select all

# dwc_otg.lpm_enable=0 console=serial0,115200 console=tty1 root=PARTUUID=12345678-02 rootfstype=ext4 elevator=deadline fsck.repair=yes rootwait
dwc_otg.lpm_enable=0 console=serial0,115200 console=tty1 root=PARTUUID=87654321-02 rootfstype=ext4 elevator=deadline fsck.repair=yes rootwait
# dwc_otg.lpm_enable=0 console=serial0,115200 console=tty1 root=/dev/mmcblk0p2 rootfstype=ext4 elevator=deadline fsck.repair=yes rootwait

Even better would be to have a couple of scripts that simply writes (echo) a single boot line to /boot/cmdline.txt for the desired device to boot:

boot-1:

Code: Select all

#!/bin/bash

sudo echo "dwc_otg.lpm_enable=0 console=serial0,115200 console=tty1 root=PARTUUID=12345678-02 rootfstype=ext4 elevator=deadline fsck.repair=yes rootwait" > /boot/cmdline.txt

boot-2:

Code: Select all

#!/bin/bash

sudo echo "dwc_otg.lpm_enable=0 console=serial0,115200 console=tty1 root=PARTUUID=87654321-02 rootfstype=ext4 elevator=deadline fsck.repair=yes rootwait" > /boot/cmdline.txt

boot-sd:

Code: Select all

#!/bin/bash

sudo echo "dwc_otg.lpm_enable=0 console=serial0,115200 console=tty1 root=/dev/mmcblk0p2 rootfstype=ext4 elevator=deadline fsck.repair=yes rootwait" > /boot/cmdline.txt

After running the appropriate script (or editing /boot/cmdline.txt), reboot.
Last edited by RonR on Sun Apr 22, 2018 7:30 pm, edited 3 times in total.

n67
Posts: 938
Joined: Mon Oct 30, 2017 4:55 pm

Re: USB Booting with 2 USB drives

Sun Apr 22, 2018 7:00 pm

OP (Matt Penfield) wrote:
When I connect a second USB drive it no longer boots, and I think this is because the Pi is trying to boot from the second drive, rather than the SSD.
I believe that the sentence quoted above makes the analysis in the response immediately preceding this one moot.

I believe that OP's situation is that he has two USB devices (drives) - only one of which is bootable.
The problem is that if both are plugged in at boot time, the boot code frequently or always tried to boot from the wrong one (the one that is not bootable) and fails, leaving the system in an unbooted (i.e., crashed) state.

If both devices were bootable, then the end state of booting the "wrong" one is that the system would still be booted - i.e., would still be up and running (some version of) some OS.

The easiest solution to OP's problem is simply not to have the 2nd device connected at boot time. Plug it in after the system is up and running. This is the most straightforward solution if you don't boot/reboot your system very often.

The other way to go, of course, is to mess with UUIDs - as has been suggested above.
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andrum99
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Joined: Fri Jul 20, 2012 2:41 pm

Re: USB Booting with 2 USB drives

Sun Apr 22, 2018 9:51 pm

According to https://www.raspberrypi.org/documentati ... ootflow.md, the Pi should check each USB mass storage device for bootcode.bin, then boot from the first one on which it finds this file.

It is possible that with 2 USB devices connected, the second drive is taking longer to become ready for some reason. You can extend the time that the Pi waits for USB devices to become ready by programming a bit in the OTP memory in the Pi by adding a line containing "program_usb_timeout=1" to the config.txt file, then booting with that config.txt once. The easiest way to do this programming is to boot from SD card once. All subsequent boots will then wait for 5 seconds for USB devices to become ready, instead of 2 seconds.

It should also be noted that not all USB mass storage devices can successfully boot a Pi. Discovering which do is a matter of trial and error, since there is currently no hardware compatibility list. Or post a message asking if someone else has successfully booted from your intended boot device on one of this website's forums.

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HawaiianPi
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Location: Aloha, Oregon USA

Re: USB Booting with 2 USB drives

Sun Apr 22, 2018 11:42 pm

n67 wrote:
Sun Apr 22, 2018 7:00 pm
I believe that OP's situation is that he has two USB devices (drives) - only one of which is bootable.
The problem is that if both are plugged in at boot time, the boot code frequently or always tried to boot from the wrong one...
Missed the first reply to this thread, eh?

I have no problem USB booting an SSD with an additional USB drive connected. Raspberry Pi3B and 3B+ with Raspbian imaged SSD and non-boot FAT32 flash drive (no boot SD card). Both systems boot from SSD every time, even when it's detected last (mounted as /dev/sdb).

Of course this assumes the OP is booting with no SD card. As I said in my reply above we need more information from the OP.

n67 wrote:
Sun Apr 22, 2018 7:00 pm
The easiest solution to OP's problem is simply not to have the 2nd device connected at boot time.
That's not a solution.
My mind is like a browser. 27 tabs are open, 9 aren't responding,
lots of pop-ups, and where is that annoying music coming from?

n67
Posts: 938
Joined: Mon Oct 30, 2017 4:55 pm

Re: USB Booting with 2 USB drives

Mon Apr 23, 2018 12:25 am

HP wrote:
Missed the first reply to this thread, eh?
No, but I just re-read it now.

No actual content there, is there? Just your speculation as to what OP's real situation is.
One man's speculation is as good as another's...

Besides, my post was directed at RonR, not you.
"L'enfer, c'est les autres"

G fytc hsqr rum umpbq rm qyw rm rfc kmbq md rfgq dmpsk:

Epmu Sn!

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RonR
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Location: US

Re: USB Booting with 2 USB drives

Mon Apr 23, 2018 2:32 am

n67 wrote:
Mon Apr 23, 2018 12:25 am
Besides, my post was directed at RonR, not you.

The solution I outlined works reliably regardless of the number of USB devices connected and regardless of whether or not they are bootable.

Matt Penfold
Posts: 9
Joined: Thu Mar 09, 2017 4:18 pm

Re: USB Booting with 2 USB drives

Mon Apr 23, 2018 9:03 am

Thanks everyone. I now have the Pi booting from the correct drive using the cmdline fix.

ephestione
Posts: 49
Joined: Wed Aug 15, 2018 10:46 am

Re: USB Booting with 2 USB drives

Sun Jul 21, 2019 11:19 am

HawaiianPi wrote:
Sun Apr 22, 2018 11:24 am
If you are using a bootcode.bin only SD card, then that's your problem (bootcode.bin tries to boot the first USB drive it finds, and fails if it's not a boot drive). There is no way to fix that without a new bootcode.bin (modified to address that issue).
I've been devouring info about USB boot on these fora and everywhere else, and several posts by you, other than this one, said that the bootcode.bin method had this issue so I left is as the very last resort.

I have 3x 3B e 1x 3B+, and I have two kingston pendrives (a datatraveler G4 32GB, and a DT50 32gb) that boot correctly with the 3B+ and one of the 3B's, while they won't boot with the remaining two 3B's (one of which has the same hardware revision # of the booting 3B... weird). Basically all of them have at least another USB drive plugged in.
I also tested a Datatraveler 100 G3 32GB, which correctly boots on the 3B+ and the other 3B, but strangely it is EXTREMELY slow in read/write speed when used as system drive (even if it's got great results in CrystalDiskMark), we're talking about up to 15 seconds of delay before, say, htop pops up, so I returned that one.

I just tried the bootcode.bin method on one of the two non-compliant 3B's, where there's the OS pendrive and another FAT32 one, I wouldn't know which one is seen first as only the non-boot pendrive has an activity led, but I tested several reboots and each time it works.
Also, at boot I see that the activity led of the non-boot pendrive blinks for a while, after which the boot proceeds normally.
Does it mean the non-boot pendrive is found first? And since there's no boot partition in it, the 3B checks for the other pendrive? I think so, because the non-boot pendrive is then associated to /dev/sda, while the boot pendrive is /dev/sdb.

So, maybe, the bootcode.bin method has been fixed in that it will recurse each drive to look for a boot partition.

In this case you might want to test it yourself with the current latest bootcode.bin from github, and update your posts around the web to let new readers know of the good news ;)

rivaldid
Posts: 5
Joined: Thu Apr 28, 2016 12:12 pm

Re: USB Booting with 2 USB drives

Fri Oct 23, 2020 1:27 pm

I have your right scenario, RPi3B+ with ssd on Geekworm X820 and a raid box usb.
So when I boot up rpi see 2 usb devices, one for os and one for the data.
Of course only one have the boot loader, if I boot up with both connected my rpi don't boot.
To have it working I have to disconnect the usb of the data device, and connect it after.
I have red all this thread, I just don't understand your solution. Exactly what you have done on bootcode.bin?

LTolledo
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Re: USB Booting with 2 USB drives

Fri Oct 23, 2020 2:03 pm

I have booted an RPi3B+ with 6 drives (1 bus powered and 5 self powered)
the bus powered drive has its UUID "registered" in fstab as its the boot drive
the other 5 are not (but auto-mounted by desktop)
my RPi3B+ always boots as expected....

also did a microSD boot RPi3B with 5 drives (1 bus powered and 4 self powered drives)
the bus powered drive has its UUID "registed" in fstab
the 4 other self powered drives are not, but are auto-mounted by desktop
the RPi3B boots as expected....
"Don't come to me with 'issues' for I don't know how to deal with those
Come to me with 'problems' and I'll help you find solutions"

Some people be like:
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rivaldid
Posts: 5
Joined: Thu Apr 28, 2016 12:12 pm

Re: USB Booting with 2 USB drives

Fri Oct 23, 2020 2:45 pm

LTolledo wrote:
Fri Oct 23, 2020 2:03 pm
I have booted an RPi3B+ with 6 drives (1 bus powered and 5 self powered)
the bus powered drive has its UUID "registered" in fstab as its the boot drive
the other 5 are not (but auto-mounted by desktop)
my RPi3B+ always boots as expected....

also did a microSD boot RPi3B with 5 drives (1 bus powered and 4 self powered drives)
the bus powered drive has its UUID "registed" in fstab
the 4 other self powered drives are not, but are auto-mounted by desktop
the RPi3B boots as expected....
My installation have the partuuid written in fstab, as I read raspberry don't recognize the uuid and have to leave partuuid. So this is not an issue. I'm using OMV5 and mouting the device from it, it also been written into fstab as /dev/disk/by-label/DATA, since data is my usb on raid box device.
Booting my rpi with this usb data connected cause me this impossibility to boot.

I think the boot process triggered by the raspberry is stopped by the data usb device that don't have a boot section. I'm trying to understand why the root parameter in cmdline.txt in which I tell where the root is located using the right partuuid, does not work as expected.


rivaldid
Posts: 5
Joined: Thu Apr 28, 2016 12:12 pm

Re: USB Booting with 2 USB drives

Thu Oct 29, 2020 11:06 pm

Mates, I solved this issue. As I have read Raspberry can have power issue with certain devices, it's not properly an issue with the device alimentation because in my case my device has his own alimentation. The issue must be with the usb port alimentation on the board, some usb devices answer slowly and make kernel panic because he boot with a missing device because there is connected but still not powered. To solve this issue you have to add an sd with fat32 formatted and with a file bootcode.bin that tell Raspberry to wait until the device is really ready.
Regards.

Dan1jel
Posts: 38
Joined: Wed Aug 08, 2018 6:21 pm
Location: Sweden

Re: USB Booting with 2 USB drives

Mon Nov 02, 2020 9:06 am

Well i tried this cmdline and my Raspberry still won't boot sometimes. I have an usb with raspOS, and a usb hard drive as server. Sometimes it boots, and sometime it fails. How can I specify what usb to boot on so this won't happen in the future?!

Edit: forgot typ say what device I had. Raspberry 3B

LTolledo
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Re: USB Booting with 2 USB drives

Mon Nov 02, 2020 9:47 am

the boot specifications are in /boot/cmdline.txt and /etc/fstab

verify the PARTUUID for the drives to see if it matches the drive you want to boot from.
"Don't come to me with 'issues' for I don't know how to deal with those
Come to me with 'problems' and I'll help you find solutions"

Some people be like:
"Help me! Am drowning! But dont you dare touch me nor come near me!"

Dan1jel
Posts: 38
Joined: Wed Aug 08, 2018 6:21 pm
Location: Sweden

Re: USB Booting with 2 USB drives

Mon Nov 02, 2020 12:02 pm

LTolledo wrote:
Mon Nov 02, 2020 9:47 am
the boot specifications are in /boot/cmdline.txt and /etc/fstab

verify the PARTUUID for the drives to see if it matches the drive you want to boot from.
This is my fstab

Code: Select all

proc            /proc           proc    defaults          0       0
PARTUUID=569fe58b-01  /boot           vfat    defaults          0       2
PARTUUID=569fe58b-02  /               ext4    defaults,noatime  0       1
UUID=0184839a-475e-40ff-924f-950469130a67 /server ext4 defaults,nofail 0 0
# a swapfile is not a swap partition, no line here
#   use  dphys-swapfile swap[on|off]  for that
And this is my cmdline:

Code: Select all

console=serial0,115200 console=tty1 root=PARTUUID=569fe58b-02 rootfstype=ext4 elevator=deadline fsck.repair=yes rootwait quiet splash plymouth.ignore-serial-consoles
#console=serial0,115200 console=tty1 root=PARTUUID=569fe58b-01 rootfstype=ext4 elevator=deadline fsck.repair=yes rootwait quiet splash plymouth.ignore-serial-consoles
#console=serial0,115200 console=tty1 root=PARTUUID=ae819627-7dc7-4e0d-a4ea-33748d1d63b9 rootfstype=ext4 elevator=deadline fsck.repair=yes rootwait quiet splash plymouth.ignore-serial-consoles

LTolledo
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Location: Anime Heartland

Re: USB Booting with 2 USB drives

Mon Nov 02, 2020 12:43 pm

the cmdline.txt should be 1 line only...

this is how it looks like in my system

Code: Select all

console=serial0,115200 console=tty1 root=PARTUUID=ea00e4c8-02 rootfstype=ext4 elevator=deadline fsck.repair=yes rootwait
"Don't come to me with 'issues' for I don't know how to deal with those
Come to me with 'problems' and I'll help you find solutions"

Some people be like:
"Help me! Am drowning! But dont you dare touch me nor come near me!"

Dan1jel
Posts: 38
Joined: Wed Aug 08, 2018 6:21 pm
Location: Sweden

Re: USB Booting with 2 USB drives

Mon Nov 02, 2020 1:05 pm

LTolledo wrote:
Mon Nov 02, 2020 12:43 pm
the cmdline.txt should be 1 line only...

this is how it looks like in my system

Code: Select all

console=serial0,115200 console=tty1 root=PARTUUID=ea00e4c8-02 rootfstype=ext4 elevator=deadline fsck.repair=yes rootwait
But I did as this info stated, what is right and what is wrong? I want my Raspberry to always boot the same usb :/
RonR wrote:
Sun Apr 22, 2018 6:26 pm
Matt Penfold wrote:
Sun Apr 22, 2018 10:38 am
I am getting my Pi3 to boot Raspbian Stretch OK when I have just one USB drive (an SSD) connected. When I connect a second USB drive it no longer boots, and I think this is because the Pi is trying to boot from the second drive, rather than the SSD.

Is there a way to have two USB drivers attacked and specify what USB drive to boot from?

First, see:
viewtopic.php?f=29&t=196778

Then, edit your /boot/cmdline.txt to contain a line for each bootable device. Comment out (#) all lines except the one you wish to boot (do not have any blank lines):

Code: Select all

# dwc_otg.lpm_enable=0 console=serial0,115200 console=tty1 root=PARTUUID=12345678-02 rootfstype=ext4 elevator=deadline fsck.repair=yes rootwait
dwc_otg.lpm_enable=0 console=serial0,115200 console=tty1 root=PARTUUID=87654321-02 rootfstype=ext4 elevator=deadline fsck.repair=yes rootwait
# dwc_otg.lpm_enable=0 console=serial0,115200 console=tty1 root=/dev/mmcblk0p2 rootfstype=ext4 elevator=deadline fsck.repair=yes rootwait

Even better would be to have a couple of scripts that simply writes (echo) a single boot line to /boot/cmdline.txt for the desired device to boot:

boot-1:

Code: Select all

#!/bin/bash

sudo echo "dwc_otg.lpm_enable=0 console=serial0,115200 console=tty1 root=PARTUUID=12345678-02 rootfstype=ext4 elevator=deadline fsck.repair=yes rootwait" > /boot/cmdline.txt

boot-2:

Code: Select all

#!/bin/bash

sudo echo "dwc_otg.lpm_enable=0 console=serial0,115200 console=tty1 root=PARTUUID=87654321-02 rootfstype=ext4 elevator=deadline fsck.repair=yes rootwait" > /boot/cmdline.txt

boot-sd:

Code: Select all

#!/bin/bash

sudo echo "dwc_otg.lpm_enable=0 console=serial0,115200 console=tty1 root=/dev/mmcblk0p2 rootfstype=ext4 elevator=deadline fsck.repair=yes rootwait" > /boot/cmdline.txt

After running the appropriate script (or editing /boot/cmdline.txt), reboot.

LTolledo
Posts: 6657
Joined: Sat Mar 17, 2018 7:29 am
Location: Anime Heartland

Re: USB Booting with 2 USB drives

Mon Nov 02, 2020 1:32 pm

is your system "multi-boot" or "single boot"
"Don't come to me with 'issues' for I don't know how to deal with those
Come to me with 'problems' and I'll help you find solutions"

Some people be like:
"Help me! Am drowning! But dont you dare touch me nor come near me!"

Dan1jel
Posts: 38
Joined: Wed Aug 08, 2018 6:21 pm
Location: Sweden

Re: USB Booting with 2 USB drives

Mon Nov 02, 2020 2:33 pm

LTolledo wrote:
Mon Nov 02, 2020 1:32 pm
is your system "multi-boot" or "single boot"
It is single boot but with one usb stick (os) and one harddrive (storage/media)

Edit : typo

RonR
Posts: 2839
Joined: Tue Apr 12, 2016 10:29 pm
Location: US

Re: USB Booting with 2 USB drives

Tue Nov 03, 2020 1:45 am

Dan1jel wrote:
Mon Nov 02, 2020 1:05 pm
RonR wrote:
Sun Apr 22, 2018 6:26 pm
Matt Penfold wrote:
Sun Apr 22, 2018 10:38 am
I am getting my Pi3 to boot Raspbian Stretch OK when I have just one USB drive (an SSD) connected. When I connect a second USB drive it no longer boots, and I think this is because the Pi is trying to boot from the second drive, rather than the SSD.

Is there a way to have two USB drivers attacked and specify what USB drive to boot from?

First, see:
viewtopic.php?f=29&t=196778

Then, edit your /boot/cmdline.txt to contain a line for each bootable device. Comment out (#) all lines except the one you wish to boot (do not have any blank lines):

Code: Select all

# dwc_otg.lpm_enable=0 console=serial0,115200 console=tty1 root=PARTUUID=12345678-02 rootfstype=ext4 elevator=deadline fsck.repair=yes rootwait
dwc_otg.lpm_enable=0 console=serial0,115200 console=tty1 root=PARTUUID=87654321-02 rootfstype=ext4 elevator=deadline fsck.repair=yes rootwait
# dwc_otg.lpm_enable=0 console=serial0,115200 console=tty1 root=/dev/mmcblk0p2 rootfstype=ext4 elevator=deadline fsck.repair=yes rootwait

Even better would be to have a couple of scripts that simply writes (echo) a single boot line to /boot/cmdline.txt for the desired device to boot:


After running the appropriate script (or editing /boot/cmdline.txt), reboot.

The script you've proposed has existed for years.

See: sdc-boot:
sdc-boot provides a convenient way to select which attached device will be booted.

Usage syntax is:

sdc-boot [ /dev/sdX2 | /dev/mmcblk0p2 | hhhhhhhh-02 | hhhhhhhh-hhhh-hhhh-hhhh-hhhhhhhhhhhh ]

/dev/sdX2 is a USB device

/dev/mmcblk0p2 is the SD card

hhhhhhhh-02 | hhhhhhhh-hhhh-hhhh-hhhh-hhhhhhhhhhhh is a device identified by its PARTUUID

If no device is specified, the currently selected boot device will be displayed.

Dan1jel
Posts: 38
Joined: Wed Aug 08, 2018 6:21 pm
Location: Sweden

Re: USB Booting with 2 USB drives

Tue Nov 03, 2020 7:31 pm

RonR wrote:
Tue Nov 03, 2020 1:45 am
Dan1jel wrote:
Mon Nov 02, 2020 1:05 pm
RonR wrote:
Sun Apr 22, 2018 6:26 pm


First, see:
viewtopic.php?f=29&t=196778

Then, edit your /boot/cmdline.txt to contain a line for each bootable device. Comment out (#) all lines except the one you wish to boot (do not have any blank lines):

Code: Select all

# dwc_otg.lpm_enable=0 console=serial0,115200 console=tty1 root=PARTUUID=12345678-02 rootfstype=ext4 elevator=deadline fsck.repair=yes rootwait
dwc_otg.lpm_enable=0 console=serial0,115200 console=tty1 root=PARTUUID=87654321-02 rootfstype=ext4 elevator=deadline fsck.repair=yes rootwait
# dwc_otg.lpm_enable=0 console=serial0,115200 console=tty1 root=/dev/mmcblk0p2 rootfstype=ext4 elevator=deadline fsck.repair=yes rootwait

Even better would be to have a couple of scripts that simply writes (echo) a single boot line to /boot/cmdline.txt for the desired device to boot:


After running the appropriate script (or editing /boot/cmdline.txt), reboot.

The script you've proposed has existed for years.

See: sdc-boot:
sdc-boot provides a convenient way to select which attached device will be booted.

Usage syntax is:

sdc-boot [ /dev/sdX2 | /dev/mmcblk0p2 | hhhhhhhh-02 | hhhhhhhh-hhhh-hhhh-hhhh-hhhhhhhhhhhh ]

/dev/sdX2 is a USB device

/dev/mmcblk0p2 is the SD card

hhhhhhhh-02 | hhhhhhhh-hhhh-hhhh-hhhh-hhhhhhhhhhhh is a device identified by its PARTUUID

If no device is specified, the currently selected boot device will be displayed.
So I need to have an SD card that re-direct to my USB for it to boot... Because that is the info I read. Or am I completely off?

RonR
Posts: 2839
Joined: Tue Apr 12, 2016 10:29 pm
Location: US

Re: USB Booting with 2 USB drives

Tue Nov 03, 2020 7:46 pm

Dan1jel wrote:
Tue Nov 03, 2020 7:31 pm
So I need to have an SD card that re-direct to my USB for it to boot... Because that is the info I read. Or am I completely off?

Raspberry Pi bootloaders don't support selecting a specific boot device. One solution to this limitation is using an SD card to redirect the booting (Running Raspbian from USB Devices : Made Easy) to a specific device. Another is MutliBoot. And there are others such as NOOBS and PINN.

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