Install Alpine Linux on a Raspberry PI using macOS

May 5, 2019

The software and hardware used for this HOWTO are:

Alpine Linux 3.8.4, armhf
Raspberry Pi 3 Model B, and:
1. USB keyboard
2. TV with HDMI input and an HDMI cable
3. MicroUSB 5V adapter as close to 2.5A as you can find (I used a 2A phone charger.)
macOS Mojave 10.14.4 (diskutil)
Samsung 32GB microSD
Vivitar microSD card reader

Step 1. Partition the microSD with your Mac and unzip install.

Use⊕ Note to self: 3.9.3 is packaged with the golang programs compiled by 1.11 allocate an unreasonable amount of virtual memory issue. armhf 3.8.4 or arm7 3.9.3 (armhf 3.9.3 won't boot on a Pi).

Make sure you know for sure which disk is the microSD. If you're not sure, don't follow these steps—you could lose all the data on your Mac.


    diskutil list
    diskutil partitionDisk disk2 MBR FAT32 VOL1 256MB "Free Space" VOL2 R
    
    export U=http://dl-cdn.alpinelinux.org/alpine/v3.8/releases/armhf
    export F=alpine-rpi-3.8.4-armhf.tar.gz
    curl $U/$F -o ~/Downloads/$F
    curl $U/$F.sha256 -o ~/Downloads/$F.sha256
    cd ~/Downloads/
    shasum -c alpine-rpi-3.8.4-armhf.tar.gz.sha256
    
    cd /Volumes/VOL1
    tar xzvf ~/Downloads/alpine-rpi-3.8.4-armhf.tar.gz
    
    cat>usercfg.txt<<EOF
    # On the Pi, the GPU and the CPU share RAM.  This is a headless install, so 
    # give the GPU the least amount of RAM it can get by with (16MB).
    # This also triggers the Pi to use a cutdown version of the firmware (start_cd.elf).
    gpu_mem=16
    
    # Turn off audio and bluetooth.  (Note "dt" stands for device tree.)
    dtparam=audio=off,pi3-disable-bt
    
    # Enable mini UART as serial port (/dev/ttyS0).  
    # Also, fixes VideoCore IV (aka the GPU or the VPU) frequency to 250MHz.
    enable_uart=1
    EOF
    
    cd ~
    # unmount microSD and remove microSD card reader from the Mac

Step 2. Create a Linux and a Linux swap partition on the Raspberry Pi.

The macOS ⊕ diskutil listFilesystems diskutil does not provide the Linux format partition type.


    # Put the microSD in the Raspberry Pi, then plug in keyboard, TV and the power supply.
    # username = root (you won't need a password)
    fdisk /dev/mmcblk0
    # Use the following inputs:
    # echo a     # Mark the DOS partition as bootable.
    # echo 1 
    # echo n     # new partition ... 
    # echo p     # ... is a primary partition
    # echo 2     # ... is the 2nd partition
    # echo       # ... with a default first sector
    # echo +30G  # ... and is 30GB big. (This leaves 1.1GB for the swap partition.)
    # echo n     # new partition ...
    # echo p     # ... is a primary partition
    # echo 3     # ... is the 3rd partition
    # echo       # ... with a default first sector
    # echo       # ... and a default last sector
    # echo t     # the partition type ... 
    # echo 3     # ... of the third partition
    # echo 82    # ... is Linux swap
    # echo p     # print the partition table ...
    # echo w     # ... and if it looks good, write it to disk
    # ignore "Resource busy" warning
    
    reboot

Configure ⊕ The key step here is to edit the apk repositories manually and to type in the repository path correctly.the Pi as suits your environment—the config I used is listed below.


    # login as root again
    
    setup-alpine
    # us                # keyboard
    # us
    # tallis            # hostname
    # eth0
    # 192.168.30.11     # static IP
    # 255.255.255.0     # netmask
    # 192.168.30.1      # gateway
    # done
    # no                # no manual network config
    # eventarelli.com   # domain
    # 192.168.30.1      # DNS server
    # s3cr3t            # new root password
    # s3cr3t
    # US/Eastern        # timezone
    # none              # no proxy
    # e                 # edit apk repositories file manually
    #                   # delete existing line "/media/..." and replace with:
    #                   # http://dl-cdn.alpinelinux.org/alpine/v3.8/main 
    #                   # :wq
    # openssh
    # chrony
    # none              # don't store configs
    # none              # don't create an apk cache
    
    mkswap /dev/mmcblk0p3
    
    apk add e2fsprogs
    # you should see five packages installed: libuuid, libblkid, libcom_err, e2fsprogs-libs, and e2fsprogs.
    mkfs.ext4 /dev/mmcblk0p2

Step 3: Install Alpine on the Linux partition and bind mount /boot directory.

Edit the cmdline.txt ⊕ After the Linux partition is setup, the Pi still boots from the DOS partition, which means it loads the kernel, initramfs, and modloop images from the DOS /boot directory. When the kernel boots, it reads command line options from cmdline.txt (which you can check with dmesg | grep command), and sets the root filesystem to be the Linux partition. We bind mount the Linux /boot to the DOS /boot so any Alpine upgrade that affects the contents of the /boot directory (for example, a new kernel) will be written to the DOS partition. on the DOS partition (mmcblk0p1) to configure the kernel to use the Linux partition (mmcblk0p2) as the root file system.


    mkdir /stage
    mount /dev/mmcblk0p2 /stage
    setup-disk -m sys /stage
    # ignore all extlinux errors, the Pi doesn't need that program
    # ignore note that you might need to "fix the MBR".
    
    echo /dev/mmcblk0p1 /media/mmcblk0p1 vfat defaults 0 0 >> /stage/etc/fstab
    
    # point root to 2nd partition
    mount -o remount,rw /media/mmcblk0p1
    sed -i '$ s/$/ root=\/dev\/mmcblk0p2/' /media/mmcblk0p1/cmdline.txt
    cat /media/mmcblk0p1/cmdline.txt
    modules=loop,squashfs,sd-mod,usb-storage quiet dwc_otg.lpm_enable=0 console=tty1 root=/dev/mmcblk0p2
    
    
    echo /media/mmcblk0p1/boot /boot none defaults,bind 0 0 >> /stage/etc/fstab
    
    reboot

Install Alpine Linux on a Raspberry PI using macOS

Step 1. Partition the microSD with your Mac and unzip install.

Step 2. Create a Linux and a Linux swap partition on the Raspberry Pi.

Step 3: Install Alpine on the Linux partition and bind mount /boot directory.

Resources

Links