alpine linux dualboot

 https://wiki.alpinelinux.org/wiki/Setting_up_disks_manually#Manual_partitioning

https://wiki.alpinelinux.org/wiki/Dualbooting

 

apk add e2fsprogs mkfs.ext4 /dev/sdXY 

mount -t ext4 /dev/sdXY /mnt

mount boot/esp partition to /boot

setup alpine 

 say no to disk,config,and cache options

setup-disk -m sys /mnt

gksudo gedit /etc/grub.d/40_custom

#!/bin/sh
echo "Adding Alpine" >&2
cat << EOF
menuentry "Alpine Linux" {
 set root=(hd0,3)
 linux /boot/vmlinuz-lts root=UUID=8de6973a-4a8c-40ed-b710-c4e2b42d6b7a modules=sd-mod,usb-storage,ext4 quiet
 initrd /boot/initramfs-lts
}
EOF

on systemd-boot usage 

copy vmlinuz-lts and initramfs-lts to / of $ESP if its not mounted in setup 

get UUID using sudo blkid and find alpine partiiton (careful with PARTUUID looks same)

nano/vi  /boot/loader/entries/alpine.conf

------------------------------------------------------------------------------

title alpine linix
linux /vmlinuz-lts
initrd /initramfs-lts
options root=UUID=2e5bf9f5-4dde-4c3f-aed4-50fbbf886be2 modules=sd-mod,usb-storage,ext4 quiet

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