how to boot from usb?

[reallaowu]

my cm5-laptop can not start, I use Etcher to program ubuntu img to a USB flash,
but I do not kown how to start from the USB flash,
And if cm5-laptop start from the USB flash, how do I format the EMMC, is there some doc for starter?

[Rock]

@reallaowu CM5 laptop currently only supports USB 2.0

[Rock]

@george I'm really looking forward to seeing you compose an official and detailed guide for installing Ubuntu 24.04 via USB2.0

[reallaowu]

@Rock usb2.0 is udb type a connector?

[Rock]

@reallaowu
This article may help you to understand the difference between usb2.0 and usb3.0

https://www.partitionwizard.com/partitionmagic/usb-2-0-vs-usb-3-0-006.html

[reallaowu]

@Rock i know the difference s between usb2 and usb3 , I just want to know how start my laptop from a external usb flash which have a ununtu img, because my laptop can not start

[george]

@reallaowu
The image is created using the ETCHER tool to a USB 2.0 USB drive, then inserted into the computer's USB interface, and turned on. The machine will boot from the USB 2.0 USB drive. After entering the system, the EMMC can be formatted using the following command.

sudo mkfs.ext4  /dev/mmcblk0

If this method still cannot boot properly, you need to dismantle the machine and force it to enter MASKROM mode to format the EMMC storage. Try following the above method first, and if it still doesn't work, I will send you a mandatory formatting method.

[reallaowu]

@george i use a usb drive to boot , it works to start ubuntu, but it seems very slow, it cost about 15 minutes still not user login interface

[reallaowu]

@george it cost about 30minutes but not enter. may it can only start from type c port by external usb drive? type a usb port is not valid?

[reallaowu]

@george I used a old usb drive , that I can enter ubuntu, but when i run "sure miss.ext4 /dev/mmcblk0" in shell
it seems not work.
/dev/mmcblk0 is apparently in used by system. will not make a file system here!

[reallaowu]

This post is deleted!

[george]

@reallaowu
This phenomenon still doesn't work properly when booting from USB, you can try it a few more times.

[reallaowu]

@george I try many times booting from usb drive, when i run "sudo mkfs.ext4 /dev/mmcblk0" in shell, it alway show "/dev/mmcblk0 is apparently in used by system. will not make a file system here!", and x64 computer find no device when cm5 laptop reboot pushing power button many times, and cm5 laptop is rebooting over and over again,

is there a different way to format the mmc to help burning img from x64 computer?

[reallaowu]

@george

mkfs -t ext4 /dev/mmcblk0

then it success