ppp拨号管理线路--自动检查默认脚本--优化版本1

#!/bin/bash

PppCheck() {
    ppp_interfaces=$(ip r | grep -o "\<ppp[0-9]\+\>" | awk -F'ppp' '{print $2}' | sort -n |uniq | awk 'BEGIN{ORS=" "}{print "ppp"$NF}')
    for iface in $ppp_interfaces; do
        if ping -I $iface -W 5 -c 2  223.5.5.5 >/dev/null 2>&1; then
            dial_ip=$(ip route show dev $iface  | awk '{print $1}')
            echo "设置默认网关为 $dial_ip (通过 $iface)"

            # 检查是否存在默认路由
            if ip route | grep -q '^default'; then
                ip route replace default via $dial_ip dev $iface
            else
                ip route add default via $dial_ip dev $iface
            fi

            if ping -W 5 -c 2  223.5.5.5 >/dev/null 2>&1; then
                echo "网络正常，修改默认网关成功"
                return 0
            else
                echo "网络不通，修改默认网关失败"
            fi
        fi
    done
    echo "网络不通，修改默认网关失败"
    return 1
}


check_ping() {
    if ping -W 5 -c 2  223.5.5.5 >/dev/null 2>&1; then
        echo "网络正常，不修改默认网关"
        return 0
    else
        echo "网络不通，修改默认网关"
        return 1
    fi
}

if check_ping; then
    exit 0
fi

mgmt_iface="$(cat /root/iface.txt 2>/dev/null)"
if [ -n "$mgmt_iface" ]; then
    if ip link show "$mgmt_iface" | grep -q "state UP"; then
        mgmt_ip=$(ip route show dev "$mgmt_iface" | awk '/^default/{print $3}')
        if [ -n "$mgmt_ip" ]; then
            echo "设置默认网关为 $mgmt_ip (通过 $mgmt_iface)"
            # 检查是否存在默认路由
            if ip route | grep -q '^default'; then
                ip route replace default via "$mgmt_ip" dev "$mgmt_iface"
            else
                ip route add default via "$mgmt_ip" dev "$mgmt_iface"
            fi
        fi
        if check_ping; then
            exit 0
        fi
    else
        echo "$mgmt_iface 接口未开启"
    fi
else
    echo "/root/iface.txt文件为空"
fi

PppCheck