nmcli-cli-bridge-add

#!/bin/bash
#
# nmcli-cli-bridge-add
#
# Copyright (c) 2019 Jun Futagawa (jfut)
#
# This software is released under the MIT License.
# http://opensource.org/licenses/mit-license.php

ECHO_OR_EXECUTE="echo"

echo_or_execute() {
    if [[ -z "${ECHO_OR_EXECUTE}" ]]; then
        echo "Applying: ${@}"
        eval ${@}
    else
        ${ECHO_OR_EXECUTE} ${@}
    fi
}

usage() {
    cat << _EOF_
Usage:

    $0 [-n] [-x] NEW_BRDIGE_IF_NAME IF_SLAVE

    Options:
        -n No interface check (Default: check interface)
        -x Run command (Default: echo only)

    Examples:
        $0 br1 eno1
        $0 br1 bond1

_EOF_
}

check() {
    local BRDIGE_IF_NAME=${1:-}
    local IF_SLAVE=${2:-}

    # Check new bridge interface
    nmcli connection show "${BRDIGE_IF_NAME}" > /dev/null 2>&1
    RET=$?
    if [[ ${RET} -eq 0 ]]; then
        echo "Error: Bridge interface \"${BRDIGE_IF_NAME}\" already exists."
        exit 1
    fi

    # Check slave interface
    nmcli connection show "${IF_SLAVE}" > /dev/null 2>&1
    RET=$?
    if [[ ${RET} -ne 0 ]]; then
       echo "Error: Slave interface \"${IF_SLAVE}\" not found."
       exit 1
   fi
}

bridge_add() {
    local BRDIGE_IF_NAME=${1:-}
    local IF_SLAVE=${2:-}

    # Bridge: STP: No, Forward Delay: 0
    echo_or_execute nmcli connection add type bridge \
        autoconnect yes ipv4.method disabled ipv6.method ignore \
        bridge.stp no bridge.forward-delay 0 \
        con-name \"${BRDIGE_IF_NAME}\" ifname \"${BRDIGE_IF_NAME}\"

    # Slave
    echo_or_execute nmcli connection modify \"${IF_SLAVE}\" connection.slave-type bridge connection.master \"${BRDIGE_IF_NAME}\"

    cat << _EOF_

# Next steps:
# -> Check bridge status
#    brctl show
#
# -> Set IP address
#    nmcli-cli-ipv4 "${BRDIGE_IF_NAME}" ...
#    nmcli-cli-ipv6 "${BRDIGE_IF_NAME}" ...
_EOF_
}

# Main
main() {
    local NO_CHECK="no"
    while getopts nxh OPT; do
        case "${OPT}" in
            "n" )
                NO_CHECK="yes" ;;
            "x" )
                ECHO_OR_EXECUTE="" ;;
            "h" )
                usage
                exit 0
                ;;
            * )
                usage
                exit 1
                ;;
        esac
    done
    shift $((OPTIND - 1))

    [[ $# -lt 2 ]] && usage && exit 1

    if [[ "${NO_CHECK}" = "no" ]]; then
        check "${@}"
    fi

    if [[ "${ECHO_OR_EXECUTE}" = "echo" ]]; then
        echo "# ${ECHO_OR_EXECUTE} only."
    fi

    bridge_add "${@}"
}

[[ ${#BASH_SOURCE[@]} = 1 ]] && main "${@}"