Classic install or sys mode on Raspberry Pi

This page documents the Classic install or sys mode installation of Alpine Linux on a Raspberry Pi. As per #12353#note_164623, the usual sys mode installation works perfectly with Raspberry Pi now.

Convert diskless to sys mode

It is also possible to switch a diskless installation to a fully disk-based installation. This is not yet formally supported, but can be done somewhat manually. This frees all the memory otherwise needed for the root filesystem, allowing more installed packages.

1. Split your SD card into two partitions: the FAT32 boot partition described above (in this example it'll be mmcblk0p1) , and a second partition to hold the root filesystem (here it'll be mmcblk0p2).
2. Boot and configure your diskless system as above, then create a root filesystem using the tool mkfs.ext4 in the e2fsprogs package:

   # apk add e2fsprogs # mkfs.ext4 /dev/mmcblk0p2

3. Now do a disk install via a mountpoint. The setup-disk script will give some errors about syslinux/extlinux, but you can ignore them. The Raspberry Pi doesn't need them to boot.

   # mkdir /stage # mount /dev/mmcblk0p2 /stage # setup-disk -o /media/mmcblk0p1/MYHOSTNAME.apkovl.tar.gz /stage

4. Add a line to /stage/etc/fstab file to mount the Pi's boot partition again as follows:

   Contents of /stage/etc/fstab

   /dev/mmcblk0p1 /media/mmcblk0p1 vfat defaults 0 0
5. Now add a root=/dev/mmcblk0p2 parameter to the Pi's boot command line, either cmdline-rpi2.txt or cmdline-rpi.txt depending on model:

   # mount -o remount,rw /media/mmcblk0p1 # sed -i '$ s/$/ root=\/dev\/mmcblk0p2/' /media/mmcblk0p1/cmdline-rpi2.txt

6. When the Pi boots next time, the contents of /boot will be ignored. It will use the kernel, initramfs, and modloop images from the FAT32 boot partition.
7. To update the kernel, initfs or modules, one could use bind mount:

   # echo /media/mmcblk0p1/boot /boot none defaults,bind 0 0 >> /etc/fstab

See also

• Raspberry Pi