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@@ -0,0 +1,155 @@
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+package main
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+
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+import (
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+ "bytes"
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+ "os/exec"
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+ "strings"
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+ "time"
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+)
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+
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+const (
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+ pingInterval = 60 * time.Second // 每10秒执行一次
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+ ipToPing = "203.34.49.130" // 这里填写要ping的IP地址
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+)
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+
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+// checkErr 输出错误信息并退出程序
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+func checkErr(err error) {
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+ if err != nil {
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+ //log.Fatalf("Error: %s", err)
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+ }
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+}
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+
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+// ping 检查是否可以到达指定的IP地址
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+func ping(ip string) bool {
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+ cmd := exec.Command("ping", "-c", "1", ip)
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+ var out bytes.Buffer
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+ cmd.Stdout = &out
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+ err := cmd.Run()
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+ output := out.String()
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+
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+ if strings.Contains(output, "1 packets transmitted, 1 received") ||
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+ strings.Contains(output, "1 packets transmitted, 1 received, 0% packet loss") {
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+ return true
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+ }
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+ return err == nil
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+}
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+
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+// checkNet 解析ip route命令的输出，返回接口与默认网关的映射以及当前默认网卡名
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+func checkNet(net string) (map[string]string, string) {
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+ var defaultNet string
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+ m := make(map[string]string)
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+ split := strings.Split(net, "\n")
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+
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+ for i := 0; i < len(split)-1; i++ {
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+ line := strings.TrimSpace(split[i])
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+ if line == "" {
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+ continue
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+ }
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+
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+ defaultNets := strings.Fields(line)
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+ if len(defaultNets) > 1 {
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+ for k := 0; k < len(defaultNets)-1; k++ {
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+ if defaultNets[k] == "dev" && defaultNets[0] == "default" {
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+ defaultNet = defaultNets[k+1]
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+ }
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+ }
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+ }
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+
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+ i2 := strings.Fields(line)
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+ if len(i2) > 1 {
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+ for j := 0; j < len(i2)-1; j++ {
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+ if i2[j] == "dev" {
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+ netName := i2[j+1]
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+ i3 := strings.Split(i2[j-1], ".")
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+ if len(i3) > 1 {
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+ ip := i3[0] + "." + i3[1] + "." + i3[2] + ".1"
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+ m[netName] = ip
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+ }
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+ }
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+ }
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+ }
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+ }
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+
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+ //fmt.Println("Routes:", m)
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+ //fmt.Println("Default Net:", defaultNet)
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+ return m, defaultNet
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+}
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+
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+// updateRoute 更新默认路由
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+func updateRoute(routes map[string]string, currentDefault, newDefault string) {
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+ if currentDefault != newDefault {
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+ cmdDel := exec.Command("ip", "route", "del", "default", "via", routes[currentDefault], "dev", currentDefault)
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+ cmdAdd := exec.Command("ip", "route", "add", "default", "via", routes[newDefault], "dev", newDefault)
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+
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+ checkErr(cmdDel.Run())
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+ checkErr(cmdAdd.Run())
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+
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+ //fmt.Printf("切换默认网卡 从 %s 到 %s\n", currentDefault, newDefault)
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+ } else {
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+ //fmt.Println("不需要切换默认网卡")
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+ }
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+}
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+
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+func main() {
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+ for {
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+ b := ping(ipToPing)
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+ if b {
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+ //fmt.Println("网络连接正常")
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+
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+ // 获取所有可用的网络接口及其默认网关
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+ cmd := exec.Command("ip", "route")
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+ var out bytes.Buffer
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+ cmd.Stdout = &out
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+ checkErr(cmd.Run())
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+ output := out.String()
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+ routes, currentDefault := checkNet(output)
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+
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+ // 判断当前默认网卡是否为 eth 网卡
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+ if !strings.Contains(currentDefault, "eth") {
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+ //fmt.Println("当前为无线网卡，正在切换到有线网卡")
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+ for k := range routes {
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+ if strings.Contains(k, "eth") {
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+ updateRoute(routes, currentDefault, k)
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+ break
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+ }
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+ }
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+ } else {
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+ //fmt.Println("当前为有线网卡，无需切换")
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+ }
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+ } else {
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+ //fmt.Println("网络未接通正在重启....")
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+
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+ // 获取所有可用的网络接口及其默认网关
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+ cmd := exec.Command("ip", "route")
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+ var out bytes.Buffer
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+ cmd.Stdout = &out
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+ checkErr(cmd.Run())
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+ output := out.String()
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+ routes, currentDefault := checkNet(output)
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+
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+ // 找到一个新的默认网卡
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+ newDefault := ""
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+ for k := range routes {
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+ if k != currentDefault {
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+ newDefault = k
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+ break
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+ }
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+ }
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+
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+ if newDefault != "" {
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+ updateRoute(routes, currentDefault, newDefault)
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+
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+ // 再次检查是否可以 ping 通
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+ b := ping(ipToPing)
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+ if b {
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+ //fmt.Println("切换网卡后网络连接正常")
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+ } else {
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+ //fmt.Println("切换网卡后仍然无法 ping 通")
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+ }
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+ } else {
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+ //fmt.Println("没有找到其他可用的网卡")
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+ }
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+ }
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+ time.Sleep(pingInterval)
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+ }
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+}
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