Back Up a Flash Memory Installation

If you have installed Alpine Linux on flash memory, such as a CF card or USB stick, you may wish to create a backup.

This procedure may also be used to migrate an Alpine Linux installation from one form of flash media to another.

Make the backup medium bootable

The backup device may be made bootable from the running system that is to be backed up, by following the instructions for setup-bootable.

Alternatively, it is also possible to boot an installation image of the same version of Alpine Linux that is to be backed up. (The version can be determined using the command "cat /etc/alpine-release".) And to follow the instructions at Create a Bootable Device to install the boot system on the backup medium (CF/USB).

Copy over the cache directory

If you have enabled APK caching for packages that are downloaded over the Internet, then you should copy over the "cache" directory from the running system to your backup medium.

For example, if the backup medium is labeled "sdb" (use the command "dmesg" to see what name your recently inserted device has received), and the system is booted from USB, you would run:

mount -t vfat /dev/sdb1 /mnt cp -a /media/usbdisk/cache /mnt/ umount /mnt

Copy over the configuration overlay file (apkovl)

All the custom configuration of your system is stored in a file named HOSTNAME.apkovl.tar.gz, where HOSTNAME is the locally configured hostname of the system (see the file /etc/hostname).

Simply copy this file to the root of your backup medium.

For example, if the backup medium is labeled "sdb" (use the command "dmesg" to see what name your recently inserted device has received), and the system is booted from USB, you would run:

mount -t vfat /dev/sdb1 /mnt cp -a /media/usbdisk/*.apkovl.tar.gz /mnt/ umount /mnt