rpi-networkconfig

#!/bin/bash

# Reconfigures Raspberry Pi networking control between systemd-networkd, dhcpcd, and Network Manager

function EnableAndStart() {
    systemctl enable $1
    systemctl start $1
}

function StopAndDisable() {
    if systemctl is-enabled $1 > /dev/null 2>&1
    then
	systemctl stop $1
	systemctl disable $1
    fi
}

function DisableDHCPcd() {
    systemctl daemon-reload
    StopAndDisable dhcpcd
    StopAndDisable wpa_supplicant
}

function DisableSystemdNetworkd() {
    systemctl daemon-reload
    StopAndDisable systemd-networkd
    StopAndDisable systemd-resolved
    echo "You may need to futz with /etc/resolv.conf, this has not been tested"
    sed -i '1d' /etc/resolvconf.conf               # For systemd-resolved
    StopAndDisable wpa_supplicant@wlan0
}

function DisableNetworkManager() {
    if dpkg-query -s network-manager > /dev/null 2>&1
    then
	StopAndDisable NetworkManager
	StopAndDisable ModemManager
    fi
}

function ReportStatus() {
    local sts="disabled"
    if systemctl is-enabled $1 > /dev/null 2>&1
    then
	sts="enabled"
    fi
    printf ">> %-16s %s\n" $1 $sts
}

if [[ ! $EUID -eq 0 ]];then
    echo "? Please run as root: sudo $0 $1 $2"
    exit 1
fi

if [ "$1" == "" ]
then
    echo -n "Use [H]elp, [D]hcpcd, [S]ystemd-networkd, or [N]network Manager [S]? " ; read $2 ans
else
    ans="$1"
fi
[ "$ans" == "" ] && ans="s"
case "$ans" in
    d*|D*)
	echo "Using dhcpcd..."
	DisableSystemdNetworkd
	DisableNetworkManager
	EnableAndStart dhcpcd
	;;

    n*|N*)
	echo "Using Network Manager..."
	DisableDHCPcd
	DisableSystemdNetworkd
	if ! dpkg-query -s NetworkManager > /dev/null 2>&1
	then
	    apt-get install network-manager
	    cp /root/nm/system-connections/* /etc/NetworkManager/system-connections
	fi
	systemctl stop NetworkManager
	echo "** Make sure that wifi is connected as desired"
	echo "** nmcli con up profilename"
	EnableAndStart NetworkManager
#	EnableAndStart ModemManager
	;;

    s*|S*)
	echo "Using systemd-networkd..."
	DisableDHCPcd
	DisableNetworkManager
	fn="/etc/systemd/network/10-eth0.network"
	if [ ! -e $fn ]
	then
	    echo "Creating $fn..."
	    cat > $fn <<EOF
[Match]
Name=eth0

[Network]
DHCP=Yes
LinkLocalAddressing=No
IPv4LL=false

[DHCP]
UseDomains=yes
EOF
	fi
	fn="/etc/systemd/network/11-wlan0.network"
	if [ ! -e $fn ]
	then
	    echo "Creating $fn..."
	    cat > $fn <<EOF

[Match]
Name=wlan0

[Network]
DHCP=ipv4

[DHCP]
RouteMetric=20
UseDomains=yes
EOF
	fi
	sed -i '1i resolvconf=NO' /etc/resolvconf.conf               # For systemd-resolved
	ln -sf /run/systemd/resolve/resolv.conf /etc/resolv.conf     # ...
	EnableAndStart wpa_supplicant@wlan0
	EnableAndStart systemd-networkd
	EnableAndStart systemd-resolved
	;;

    h*|H*)
	echo "Current Network Configuration status"
	ReportStatus dhcpcd
	ReportStatus systemd-networkd
	ReportStatus NetworkManager
	ReportStatus ModemManager
	exit
	;;
    *)
	echo "% Unrecognized network configuration selection"
	echo "% Network configuration not changed"
	exit
	;;
esac

echo ""
echo ">> Network configuration updated"
echo ">> You must reboot the system now"
echo ""