Include:Copying Alpine to Flash

The following part describes various ways how to create bootable USB stick with Alpine Linux.

Clone ISO image content to USB stick (Alpine Linux from 3.3.0 and later)

From Alpine Linux 3.3.0, the generated ISO's are a hybridISO, which means they contain a valid MBR and can be raw copied directly to the USB stick, Hard Drive (If you really know what you're doing), or burnt to a CD/DVD.

The following dd instructions follow helpful guidance from https://wiki.voidlinux.eu/Live_Images wholly or in part.

If the USB stick is in a Unix/Linux/OSX system, you will need to find out what the USB device is. There are various utilities to determine the device name (e.g. /dev/sdx) for your USB device. One way is:

$ sudo fdisk -l

If it is still unclear which is your USB's device name, in Linux you could try sudo lsblk -a ; or use parted (sudo parted -l).

Then, in order to dd the iso, ensure that your usb drive is not mounted, as various desktop environments automatically mount usb pen drives:

$ sudo umount /dev/sdx

Next, change to the directory where your Alpine .iso file is located, for example:

$ cd ~/Downloads

Warning: The following instruction will destroy data on the device being written to - be sure that you have identified your USB device name correctly first!

Then you can use dd to copy the iso to it. Change alpine.iso in the following command to the name of your .iso file; and change /dev/sdx to the name of your pen drive's device name. The following command may take a few minutes to execute:

 $ sudo dd if=alpine.iso of=/dev/sdx && sync

Copy ISO content to USB stick as individual files

Warning: We assume here sda is your USB stick which would hold bootable Alpine Linux files.

The following procesure is for Alpine Linux distribution itself, if you are using other Linux distro or other operating system you should know the best how to install syslinux and where mbr.bin file is located on your filesystem.

If you created a new partition above, format the flash medium with a FAT32 filesystem (replacing sda with your flash medium name):
apk add dosfstools
mkdosfs -F32 /dev/sda1
Install syslinux and MBR (replacing sda with your flash medium name):
apk add syslinux
dd if=/usr/share/syslinux/mbr.bin of=/dev/sda
syslinux /dev/sda1
Copy the files to the flash medium (replacing sda with your flash medium name):
mkdir -p /media/sda1 mount -t vfat /dev/sda1 /media/sda1 cd /media/cdrom cp -a .alpine-release * /media/sda1/ umount /media/sda1
(Optional) Remove any apkovl files that were transfered as part of the copy process. This should be done if you wish to have a fresh install. Replace sda with your flash medium name)
mount -t vfat /dev/sda1 /media/sda1 rm /media/sda1/*.apkovl.tar.gz umount /media/sda1

Troubleshooting

Wrong Device Name

If you cannot boot from the flash medium and you see something like:

Mounting boot media failed.
initramfs emergency recovery shell launched. Type 'exit' to continue boot

then it is likely that the device name in syslinux.cfg is wrong. You should replace the device name in this line:

append initrd=/boot/grsec.gz alpine_dev=usbdisk:vfat modules=loop,cramfs,sd-mod,usb-storage quiet

with the proper device name.

For boot from USB, the device name should be 'usbdisk' (as shown above)
For other options, you can run cat /proc/partitions to see the available disks (i.e. 'sda' or 'sdb')

Non-FAT32 Filesystems

When your flash medium is formatted with a filesystem other than FAT32, you might have to specify the necessary filesystem modules in the boot parameters.

To do so, mount the flash medium and change the syslinux.cfg file line from

append initrd=/boot/grsec.gz alpine_dev=usbdisk:vfat modules=loop,cramfs,sd-mod,usb-storage quiet

to

append initrd=/boot/grsec.gz alpine_dev=usbdisk:ext3 modules=loop,cramfs,sd-mod,usb-storage,ext3 quiet

in the case of an ext3 formatted partition. A similar procedure might apply to other filesystems (if they are supported by syslinux and the Alpine Linux kernel).