Re: Dual-stack preseeding

["Jonathan Leroy" <jonathan-ml@relkian.com>]

Mer 10 sept 2025, à 21:37, Jonathan Leroy a écrit :
> Is there a way to configure a dual-stack network interface using 
> preseeding whitout relying on things like a custom script run by 
> preseed/late_command?

FWIW, I got around the issue by adding this script as preseed/late_command:

====================================================

fix_network() {
    # Enable DHCPv4 on main interface if only IPv6 is enabled.

    # Does the system have a default IPv4 route?
    has_ipv4="$(ip -4 route show default)"
    if [ -n "${has_ipv4}" ]
    then
        echo "This system already has an IPv4 route, skipping DHCPv4" \
            "configuration."
        return
    fi

    # shellcheck disable=SC2312
    #
    #    "default via fe80::1 dev enp1s0 metric 1024 onlink pref medium"
    # => "enp1s0"
    main_iface="$(ip -6 route show default | cut -d ' ' -f 5)"
    if [ -z "${main_iface}" ]
    then
        # Should never happen as we are doing a netinstall.
        echo "Error: No IPv4 or IPv6 route found, this system network isn't" \
            "correctly configured."
        exit 1
    fi

    echo "Main network interface: ${main_iface}"

    # "-e" enable interpretation of backslash escapes (disabled by default
    # in BusyBox's sh).
    echo -e "allow-hotplug ${main_iface}\niface ${main_iface} inet dhcp\n" \
        > "/target/etc/network/interfaces.d/00-${main_iface}-dhcp"

    echo "DHCPv4 enabled on ${main_iface} interface."
}

echo "Checking network configuration..."
fix_network

====================================================

-- 
Jonathan Leroy