DNS修改器(linux+win)

前言

有需求：修改DNS服务器，主备两个，要求无脑配置

linux下修改DNS(无需root权限)

常规shell命令方法都需要linux的root权限才能执行，但我发现普通用户在图形界面改DNS也能生效，也就是说通常普通用户也是拥有修改网络配置的权限的，只是不能通过修改系统配置文件来实现，但是有其他方法，如nmcli命令

查看活动的网络连接名称

nmcli -t -f NAME con show --active

修改DNS

nmcli con mod <connection_name> ipv4.dns <dns_primary>,<dns_secondary>

刷新DNS缓存

systemd-resolve --flush-caches

代码

import subprocess
import time

def set_dns(dns_primary, dns_secondary):
    try:
        connection_name = subprocess.check_output(['nmcli', '-t', '-f', 'NAME', 'con', 'show','--active']).decode().strip()
        subprocess.run(['nmcli', 'con', 'mod', connection_name, 'ipv4.dns', f'{dns_primary},{dns_secondary}'])
        subprocess.run(['nmcli', 'con', 'down', connection_name])
        subprocess.run(['nmcli', 'con', 'up', connection_name])
        subprocess.run(['systemd-resolve', '--flush', 'caches'])
        time.sleep(10)
        try:
            dns_info = subprocess.check_output(['nmcli'], text=True)
            if dns_primary in dns_info and dns_secondary in dns_info:
                print("设置DNS配置成功")
        except subprocess.CalledProcessError as e:
            print(f"设置DNS配置失败: {e}")
            return False
    except subprocess.CalledProcessError as e:
        print(f"设置DNS配置失败: {e}")
        return False

if __name__ == "__main__":
    dns_primary = "114.114.114.114"
    dns_secondary = "8.8.8.8"
    set_dns(dns_primary, dns_secondary)
    input("按任意键退出...")
    # pyinstaller --onefile -c --uac-admin --noconfirm setDNS.py

可以用pyinstaller直接打包成linux下的可执行文件

windows下修改DNS(默认使用管理员权限打开)

遍历所有网卡，如果IP是以192开头的，则修改其DNS配置

代码

import wmi
import re
import os

def set_dns_configuration():
    try:
        wmiService = wmi.WMI()
        colNicConfigs = wmiService.Win32_NetworkAdapterConfiguration(IPEnabled=True)
        for colNicConfig in colNicConfigs:
            for ip in colNicConfig.ipaddress:
                if re.match(r'192\.', ip) is not None:
                    arrDNSServers = ['114.114.114.114', '8.8.8.8']
                    returnValue = colNicConfig.SetDNSServerSearchOrder(DNSServerSearchOrder=arrDNSServers)
                    if returnValue[0] == 0:
                        print("DNS修改成功")
                        break
                    else:
                        print("DNS修改失败")
        flushDNS = "ipconfig /flushdns"
        os.system(flushDNS)
        print("DNS配置成功")
    except Exception as e:
        print(f'程序运行错误，原因：{str(e)}')

if __name__ == "__main__":
    set_dns_configuration()
    input('按下任意键退出')
    # pyinstaller --onefile -c --uac-admin --noconfirm set_DNS_win.py

pyinstaller --onefile -c --uac-admin --noconfirm set_DNS_win.py

--uac-admin参数表示默认以管理员权限运行