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@sfan5
Last active May 11, 2024 13:51
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Create bootable systemd-nspawn containers with Alpine, Arch Linux or Ubuntu
#!/bin/bash -e
# Creates a systemd-nspawn container with Alpine
MIRROR=http://dl-cdn.alpinelinux.org/alpine
VERSION=${VERSION:-v3.19}
APKTOOLS_VERSION=2.14.4-r0
wget_or_curl () {
if command -v wget >/dev/null; then
wget -qO- "$1"
elif command -v curl >/dev/null; then
curl -Ls "$1"
else
echo "missing either curl or wget" >&2
return 1
fi
}
if [ $UID -ne 0 ]; then
echo "run this script as root" >&2
exit 1
fi
dest="$1"
if [ -z "$dest" ]; then
echo "Usage: $0 <destination>" >&2
exit 0
fi
if [ -e "$dest/usr/bin" ]; then
echo "destination already seems to contain a root file system" >&2
exit 1
fi
if [[ "$(uname -m)" =~ ^i[3456]86|x86 ]]; then
toolarch=x86
guestarch=$toolarch
[ "$(uname -m)" = x86_64 ] && guestarch=x86_64
elif [[ "$(uname -m)" =~ ^arm|aarch64 ]]; then
toolarch=armv7
guestarch=$toolarch
[ "$(uname -m)" = aarch64 ] && guestarch=aarch64
else
echo "unsupported architecture" >&2
exit 1
fi
apkdir=$(mktemp -d)
trap 'rm -rf $apkdir' EXIT
wget_or_curl "$MIRROR/latest-stable/main/$toolarch/apk-tools-static-$APKTOOLS_VERSION.apk" \
| tar -xz -C $apkdir || \
{ echo "couldn't download apk-tools, the version might have changed..." >&2; exit 1; }
$apkdir/sbin/apk.static \
-X $MIRROR/$VERSION/main -U --arch $guestarch \
--allow-untrusted --root "$dest" \
--initdb add alpine-base
mkdir -p "$dest"/{etc/apk,root}
# configure mirror
printf '%s/%s/main\n%s/%s/community\n' "$MIRROR" $VERSION "$MIRROR" $VERSION >"$dest"/etc/apk/repositories
for i in $(seq 0 10); do # https://github.com/systemd/systemd/issues/852
echo "pts/$i" >>"$dest/etc/securetty"
done
# make console work
sed '/tty[0-9]:/ s/^/#/' -i "$dest"/etc/inittab
printf 'console::respawn:/sbin/getty 38400 console\n' >>"$dest"/etc/inittab
# minimal boot services
for s in hostname bootmisc syslog; do
ln -s /etc/init.d/$s "$dest"/etc/runlevels/boot/$s
done
for s in killprocs savecache; do
ln -s /etc/init.d/$s "$dest"/etc/runlevels/shutdown/$s
done
echo ""
echo "Alpine $VERSION $guestarch container was created successfully."
#!/bin/bash -e
# Creates a systemd-nspawn container with Arch Linux
MIRROR=http://mirror.fra10.de.leaseweb.net/archlinux
ISO_DATE=latest
PKG_GROUPS="base"
wget_or_curl () {
if command -v wget >/dev/null; then
wget "$1" -O "$2"
elif command -v curl >/dev/null; then
curl -L "$1" -o "$2"
else
echo "missing either curl or wget" >&2
return 1
fi
}
if [ $UID -ne 0 ]; then
echo "run this script as root" >&2
exit 1
fi
dest="$1"
if [ -z "$dest" ]; then
echo "Usage: $0 <destination>" >&2
exit 0
fi
if [ -e "$dest/usr/bin" ]; then
echo "destination already seems to contain a root file system" >&2
exit 1
fi
[ "$(uname -m)" = x86_64 ] || { echo "unsupported architecture" >&2; exit 1; }
tarfile=$(mktemp)
trap 'rm $tarfile' EXIT
wget_or_curl "$MIRROR/iso/$ISO_DATE/archlinux-bootstrap-x86_64.tar.gz" $tarfile
mkdir -p "$dest"
tar -xzf $tarfile -C "$dest" --strip-components=1 --numeric-owner
# configure mirror
printf 'Server = %s/$repo/os/$arch\n' "$MIRROR" >"$dest"/etc/pacman.d/mirrorlist
sed '/^root:/ s|\*||' -i "$dest/etc/shadow" # passwordless login
rm "$dest/etc/resolv.conf" # systemd configures this
# https://github.com/systemd/systemd/issues/852
[ -f "$dest/etc/securetty" ] && \
printf 'pts/%d\n' $(seq 0 10) >>"$dest/etc/securetty"
# seems to be this bug https://github.com/systemd/systemd/issues/3611
systemd-machine-id-setup --root="$dest"
# install the packages
systemd-nspawn -q -D "$dest" sh -c "
pacman-key --init && pacman-key --populate
pacman -Sy --noconfirm --needed ${PKG_GROUPS}
"
echo ""
echo "Arch Linux container was created successfully (bootstrapped from $ISO_DATE)"
#!/bin/bash -e
# Creates a systemd-nspawn container with Ubuntu
CODENAME=${CODENAME:-noble}
wget_or_curl () {
if command -v wget >/dev/null; then
wget "$1" -O "$2"
elif command -v curl >/dev/null; then
curl -L "$1" -o "$2"
else
echo "missing either curl or wget" >&2
return 1
fi
}
if [ $UID -ne 0 ]; then
echo "run this script as root" >&2
exit 1
fi
dest="$1"
if [ -z "$dest" ]; then
echo "Usage: $0 <destination>" >&2
exit 0
fi
if [ -e "$dest/usr/bin" ]; then
echo "destination already seems to contain a root file system" >&2
exit 1
fi
if [ "$(uname -m)" = x86_64 ]; then
guestarch=amd64
elif [ "$(uname -m)" = aarch64 ]; then
guestarch=arm64
else
echo "unsupported architecture" >&2
exit 1
fi
rootfs=$(mktemp)
trap 'rm $rootfs' EXIT
wget_or_curl "http://cloud-images.ubuntu.com/${CODENAME}/current/${CODENAME}-server-cloudimg-${guestarch}-root.tar.xz" $rootfs
mkdir -p "$dest"
tar -xaf $rootfs -C "$dest" --numeric-owner
sed '/^root:/ s|\*||' -i "$dest/etc/shadow" # passwordless login
rm "$dest/etc/resolv.conf" # systemd configures this
# https://github.com/systemd/systemd/issues/852
[ -f "$dest/etc/securetty" ] && \
printf 'pts/%d\n' $(seq 0 10) >>"$dest/etc/securetty"
# container needs no mounts
>"$dest/etc/fstab"
# disable services and uninstall packages
systemd-nspawn -q -D "$dest" sh -c '
[ -s /etc/environment ] && . /etc/environment
for unit in ssh.service ssh.socket systemd-timesyncd systemd-networkd-wait-online systemd-resolved; do
systemctl is-enabled "$unit" && systemctl disable "$unit"
done
apt-get -qq satisfy -y --purge "Conflicts: lxcfs, lxd, snapd, cloud-init" || \
apt-get -qq purge --autoremove snapd lxcfs lxd cloud-init
'
echo ""
echo "Ubuntu $CODENAME $guestarch container was created successfully"
@Jip-Hop
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Jip-Hop commented Jan 2, 2023

Thanks for this script! Building my own based on yours :)

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