Boot from USB stick?

[srynoname]

Hello,

I'd like to boot from a USB stick or lets say boot from SD card and then run from usb stick. What's the easiest and prefererred way to do this?

Thanks for any hint!

[joan]

The boot code is read from the sd card so you can't boot from usb stick.

[srynoname]

thank you joan, I understand this. It's enough for me if then the root file system and so on is on the usb stick, so let pi boot from sd card and then let the stick take over. What's the best way to set this up?

[joan]

I have no idea.

Might be worthwhile to look through the following sort of thread.

http://raspberrypi.org/phpBB3/viewtopic.php?f=63&t=6685

[dom]

Use dd or winimage to write the image to the USB stick rather than the sdcard.
Format the sdcard as FAT and copy the files from the FAT partition of the USB stick onto the sdcard (only needs to be about 64M in size).

Change cmdline.txt on sdcard from root=/dev/mmcblk0p2 to root=/dev/sda2

[Mr.Dave]

Use dd or winimage to write the image to the USB stick rather than the sdcard.
Format the sdcard as FAT and copy the files from the FAT partition of the USB stick onto the sdcard (only needs to be about 64M in size).

Change cmdline.txt on sdcard from root=/dev/mmcblk0p2 to root=/dev/sda2

Could this also be used with a USB HDD of any size too or does the FS have to be FAT ?

(Still waiting for my Pi to arrive so picking up tips until then )

[srynoname]

Use dd or winimage to write the image to the USB stick rather than the sdcard.
Format the sdcard as FAT and copy the files from the FAT partition of the USB stick onto the sdcard (only needs to be about 64M in size).

Change cmdline.txt on sdcard from root=/dev/mmcblk0p2 to root=/dev/sda2

Works awesome and without fiddlign, perfect, thank you!
Just one problem: raspi-config can't resize the root partition in this case ): Well, gues I have to do this manually or is there an easy way to fix the problem with raspi-config? Thanks

Could this also be used with a USB HDD of any size too or does the FS have to be FAT ?

you need to initially boot from the SD card, then the external hdd can take over. FAT only required for the boot partition, for the root ext4 seems to be default.

[Mr.Dave]

Use dd or winimage to write the image to the USB stick rather than the sdcard.
Format the sdcard as FAT and copy the files from the FAT partition of the USB stick onto the sdcard (only needs to be about 64M in size).

Change cmdline.txt on sdcard from root=/dev/mmcblk0p2 to root=/dev/sda2

Works awesome and without fiddlign, perfect, thank you!
Just one problem: raspi-config can't resize the root partition in this case ): Well, gues I have to do this manually or is there an easy way to fix the problem with raspi-config? Thanks

Could this also be used with a USB HDD of any size too or does the FS have to be FAT ?[/quoite]
you need to initially boot fromt he SD card, then the external hdd can take over. FAt only required for the boot partition, for the root ext4 seems to be default.

Great thanks alot

[dom]

Works awesome and without fiddlign, perfect, thank you!
Just one problem: raspi-config can't resize the root partition in this case ): Well, gues I have to do this manually or is there an easy way to fix the problem with raspi-config? Thanks

Try:

Code: Select all

cp /usr/bin/raspi-config ~
sed -i 's/mmcblk0p2/sda2/' ~/raspi-config                                                                              
sed -i 's/mmcblk0/sda/' ~/raspi-config
sudo ~/raspi-config

Then choose the resize root partition. Not tested this version, but I did something similar in the past.

[srynoname]

Use dd or winimage to write the image to the USB stick rather than the sdcard.
Format the sdcard as FAT and copy the files from the FAT partition of the USB stick onto the sdcard (only needs to be about 64M in size).

Change cmdline.txt on sdcard from root=/dev/mmcblk0p2 to root=/dev/sda2

Works awesome and without fiddlign, perfect, thank you!
Just one problem: raspi-config can't resize the root partition in this case ): Well, gues I have to do this manually or is there an easy way to fix the problem with raspi-config? Thanks

Hmm about the resize, guess one could also put image on sd card completely, boot once, resize partition and then image the sd card, copy image to usb stick, clear sd card and put only boot stuff on it.

Edit: doms way also sounds quite well, will test it later. I forgot raspi-config is a script, not a binary application

[Joe Schmoe]

Edit: doms way also sounds quite well, will test it later. I forgot raspi-config is a script, not a binary application

The method should work just as well (well, almost) if it was a binary...

P.S. You could reduce the sed to a single invocation, like this:

sed -E 's/mmcblk0p?/sda/'

[srynoname]

thank you both, tried it with doms "original commands" and it worked fine!

[dom]

P.S. You could reduce the sed to a single invocation, like this:

sed -E 's/mmcblk0p?/sda/'

No, the second replace doesn't have the p in. (Although I'm sure there exists a single line version).

[kadamski]

Actually Joes version will replace mmcblk0 to sda and mmcblk0p2 to sda2 in one line. It will also replace mmcblk0p1 to sda1 and so on.

[dom]

Actually Joes version will replace mmcblk0 to sda and mmcblk0p2 to sda2 in one line. It will also replace mmcblk0p1 to sda1 and so on.

You are quite right.

[Joe Schmoe]

Yes. "man re_format" should tell you all about these things.

[kermitas]

Use dd or winimage to write the image to the USB stick rather than the sdcard.
Format the sdcard as FAT and copy the files from the FAT partition of the USB stick onto the sdcard (only needs to be about 64M in size).

Change cmdline.txt on sdcard from root=/dev/mmcblk0p2 to root=/dev/sda2

Thank you 'dom'.
I was very easy to boot from SD card and then operate from pendrive:).

So now I have added sdhci-bcm2708.missing_status=0 sdhci-bcm2708.sync_after_dma=0 and started long term tests to see if different webcams works more stable with rpi.

I hope that SD card is now only used for boot and system will not turn randomly to read-only - on SD card IO errors. Am I right?

[MrWareWolf]

Sadly, I can't get this to work.

I followed the directions, but I get a kernel panic.

When I make a new NORMAL sd card the cmdline.txt contains this:
dwc_otg.speed=0 dwc_otg.lpm_enable=0 root=/dev/ram0 init=/sbin/init console=ttyAMA0,115200 kgdboc=ttyAMA0,115200 console=tty1

Do I need to let it completely install to sd card (including all the network updates and all that), & then mod the cmdline file..then make the usb go thru the whole network updates and all that again??

[RaTTuS]

Sadly, I can't get this to work.

I followed the directions, but I get a kernel panic.

When I make a new NORMAL sd card the cmdline.txt contains this:
dwc_otg.speed=0 dwc_otg.lpm_enable=0 root=/dev/ram0 init=/sbin/init console=ttyAMA0,115200 kgdboc=ttyAMA0,115200 console=tty1

Do I need to let it completely install to sd card (including all the network updates and all that), & then mod the cmdline file..then make the usb go thru the whole network updates and all that again??

there are plenty of other posts about moving the rootfs
but basically
take a working SD card
and a blank USB drive [flash or HD]
duplicate the 2nd partition on the SD card to a partition on the USB drive
i.e.
dd bs=1M conv=sync,noerror if=/dev/mmcblk0p2 of=/dev/sda1
^ alter your if and of to whatever is correct for you
edit
/boot/cmdline.txt to be
dwc_otg.lpm_enable=0 root=/dev/sda1 rootfstype=ext4 elevator=deadline rootwait
[alter what is /dev/mmcblk0p2 to be /dev/sda1or what your new drive is it will not be
root=/dev/ram0
]
reboot and your away

also
http://www.raspberrypi.org/phpBB3/viewt ... 66&t=10998

[duberry]

any one know if someone posted instructions/info needed to boot from usb without sd card ?

i found this https://twitter.com/TeamRaspi/status/313721902906613760

Raspberry Pi Team ‏@TeamRaspi 18 Mar

Today I got the Raspberry Pi model A booting with no sdcard! It's booting its code from USB (from a model B!)

[dom]

any one know if someone posted instructions/info needed to boot from usb without sd card ?

i found this https://twitter.com/TeamRaspi/status/313721902906613760

Raspberry Pi Team ‏@TeamRaspi 18 Mar

Today I got the Raspberry Pi model A booting with no sdcard! It's booting its code from USB (from a model B!)

Note the following message:

you cannot boot from a mass storage device, only from a host (ie plug it into your PC and boot it directly). But it's still cool!

[Joe Schmoe]

Dom,

Are you saying that there is (at least a little bit) some credence to the claim on twitter?

The CW has always been that, despite what anyone says, you can't boot the Pi w/o an SD card.

FWIW, not that I see any real utility in this idea (I'm in the "But isn't it cool?" camp), how would one go about booting the Pi from the USB port (connected to another PC)? (That is, if there is anything to this at all...)

[dom]

Are you saying that there is (at least a little bit) some credence to the claim on twitter?

The CW has always been that, despite what anyone says, you can't boot the Pi w/o an SD card.

FWIW, not that I see any real utility in this idea (I'm in the "But isn't it cool?" camp), how would one go about booting the Pi from the USB port (connected to another PC)? (That is, if there is anything to this at all...)

That twitter post is Gordon (gsh), so is true.
The model A Raspberry Pi can be booted from a USB *host* (like a PC) running the correct software.
Not sure if this will prove useful to anyone yet.

[rpdom]

If the model A could be booted from a PC (ideally a Debian Linux system) via USB, that could make some of the bare metal testing a lot less tedious without all the switching of the SD card. Just compile appropriate image on PC and boot Pi via USB.

I expect it wouldn't be worth the effort to set up for the few people who would use it though.

[dindoun]

Really great - it works -

the job I've done:
1. raspdebian on the sdcard
2. put the sd card and the usb stick formated in ext4 - 1 partition -in the computer ( linux )
it gives :
- /dev/sdb1 ( boot ) and /dev/sdb2 for the sd
- /dev/sdf1 on the usb stick
3. dd bs=1M conv=sync,noerror if=/dev/sdb2 of=/dev/sdf1 ; sync
4. change root=/dev/mmcbl... into root=/dev/sda1

CARE WITH THE POINT 3 : AFTER of= YOU MUST PUT THE PARTITION OF THE USB STICK - NO ERROR ALLOWED.