背景：我边吃边打电话，说数据没有更新，必须赶紧解决问题！然后查了下发现xxl-job的executor没有自动注册，接管了别人的项目，我对代码不熟悉，其实我对xxl-job不是很熟悉。哈，这时候通过代码查，知道了executor的ip，但是不知道端口。其实最后发现是默认的9999操作：去服务器找服务，执行ps-ef|grepjava，找到服务进程id：23342然后执行netstat-nap|grep23342，看到LISTEN里面有四个端口，分别是8899、46276、99、99、20882，这个时候不知道在xxl-job默认端口的前提下，一一尝试，快速解决问题！总结：一些常用中间件的默认端口要记住，至少有个地方可以查询；netstat命令也用到了，只是没有深入了解它的各个参数的作用。留个坑（已填）：1.常用中间件的默认端口排列；2、以上两条命令执行后各列数据含义详解；附：该命令的一般格式为：netstat[-a][-b][-e][-f][-n][-o][-pproto][-r][-s][-x][-t][interval]option命令中各选项含义如下：-a显示所有套接字，包括正在监听的套接字。-n以数字方式显示地址和端口号。-r显示核心路由表，格式同“route-e”。-t显示当前连接卸载状态。-v显示正在进行的工作。-pproto显示由proto指定的协议的连接。-b显示创建每个连接或侦听端口所涉及的可执行程序。-e显示以太网统计信息。该选项可以与-s选项结合使用。-f显示外部地址的完全限定域名(FQDN)。-o显示与每个连接关联的拥有进程PID。-q显示所有连接、监听端口和绑定的非监听TCP端口。-s显示每个协议的统计信息。-x显示NetworkDirect连接、侦听器和共享端点。-y显示所有连接的TCP连接模板。不能与其他选项组合。interval重新显示选定的统计信息，显示之间暂停的秒数。按CTRL+C停止重新显示统计信息。如果省略，netstat将打印一次当前配置信息。[root@beijing-192-168-1-144~]#ps-ef|grepjavaroot23342125Apr24？13-20:18:20/usr/bin/java-server-Xms1024m-Xmx1024m-jar/opt/levi/sc/projects/sc-beijing-web/sc-beijing-web.jar--spring.config.location=/opt/beijing-sc-profiles/bootstrap.properties--spring.profiles.active=prod--spring.application.name=sc-beijing-web--spring.profiles.active=prod[root@beijing-192-168-1-144~]#[root@beijing-192-168-1-144~]#[root@beijing-192-168-1-144~]#[root@beijing-192-168-1-144~]#netstat-nap|grep23342tcp600:::8899:::*听23342/javatcp600:::46276:::*听23342/javatcp600:::9999:::*听23342/javatcp600:::20882:::*听23342/javatcp600192.168.1.144:46276192.168.1.144:35214已建立23342/javatcp600192.168.1.144:35488192.168.1.1.122:5672建立了23342/javatc600192.168.1.1444444444444444444444:51200192.168.1.1.233333333333333333333333342/javatccandjavatccanjavatcp600192.168.1.144:51916192.168.1.233:3307ESTABLISHED23342/javatcp600192.168.1.144:50124192.168.1.144:18701ESTABLISHED23342/javatcp600192.168.1.144:59396192.168.1.144:20881ESTABLISHED23342/javatcp600192.168.1.144:60710192.168.1.9:8848ESTABLISHED23342/javatcp600192.168.1.144:51188192.168.1.233:3307ESTABLISHED23342/javatcp600192.168.1.144:52458192.168.1.233:3307ESTABLISHED23342/javatcp65940192.168.1.144:46276192.168.1.144:60272CLOSE_WAIT23342/javatcp600192.168.1.144:49478192.168.1.233:3307已建立23342/javatcp600192.168.1.144:50626192.168.1.233:3307ESTABLISHED23342/javatcp600192.168.1.144:50800192.168.1.233:3307ESTABLISHED23342/javatcp600192.168.1.144:51340192.168.1.233:3307ESTABLISHED23342/javatcp600192.168.1.144:50858192.168.1.233:3307ESTABLISHED23342/javatcp610790192.168.1.144:46276192.168.1.144:59648CLOSE_WAIT23342/javatcp600192.168.1.144:49812192.168.1.233:3307ESTABLISHED23342/javatcp600192.168.1.144:46276192.168.1.144:37754ESTABLISHED23342/javatcp600192.168.1.144:60770192.168.1.9:8848ESTABLISHED23342/javatcp600192.168.1.144:60772192.168.1.9:8848ESTABLISHED23342/javatcp600192.168.1.144:60774192.168.1.9:8848已建立23342/javatcp600192.168.1.144:50672192.168.1.233:3307已建立23342/javatcp600192.168.1.144:49662192.168.1.233:3307ESTABLISHED23342/javatcp600192.168.1.144:51948192.168.1.233:3307ESTABLISHED23342/javatcp600192.168.1.144:38610192.168.1.9:9090ESTABLISHED23342/javatcp600192.168.1.144：50314192.168.1.233:3307建立了23342/javatcp600192.168.1.144：52582192.168.1.23333307建立了23342/javatcp6000192.168.1.1.14.1.14.144.14.14.14.1444.14.14.1n.loke46276192.168.1.144:37756ESTABLISHED23342/javatcp600192.168.1.144:52460192.168.1.233:3307ESTABLISHED23342/javatcp600192.168.1.144:60728192.168.1.9:8848ESTABLISHED23342/javatcp600192.168.1.144:51710192.168.1.233:3307已建立23342/javatcp600192.168.1.144:50784192.168.1.233:3307已建立23342/javaudp600:::46993::::*23342/javaudp600::::33620::::*23342/javaudp600::::35309::::*23342/javaudp600::::55380::::*23342/javaudp6535040:::39410:::*23342/javaunix2[]流连接9387375423342/javaunix2[]流连接9388083823342/java[root@beijing-192-168-1-144~]#[root@VM-24-4-centos~]#netstat-napActiveInternetconnections(serversandestablished)ProtoRecv-QSend-QLocalAddressForeignAddressStatePID/Programnametcp000.0.0.0:63790.0.0.0:*LISTEN27989/redis-serverTCP000.0.0.0:800.0.0.0:*收听19523/nginx:主tcp000.0.0.0:220.0.0.0:*监听1325/sshdtcp000.0.0.0:80880.0.0.0:*监听19523/nginx:主tcp000.0.0.0:8880.0.0.0:*LISTEN19523/nginx:mastertcp000.0.0.0:88880.0.0.0:*LISTEN2449/pythontcp00127.0.0.1:250.0.0.0:*LISTEN1277/mastertcp0010.0.24.4:8888218.102.101.54:22880ESTABLISHED2449/pythontcp0010.0.24.4:888892.255.85.183:60320ESTABLISHED2449/pythontcp0010.0.24.4:8888188.92.77.15:64226ESTABLISHED2449/pythontcp0010.0.24.4:45372169.254.0.138:8086已建立25391/tat_agenttcp0010.0.24.4:888880.82.70.168:53558建立了2449/PythonTCP0010.0.0.24.4:888861.52.78.196:38156建立了2449/PythonTCP0001010.0.24.24.24.4:88888888888888888888888344444444444444444444444444444444444444444444444444444444444444444444444444444444444444444444444444444444.44.43.11444444444444.888892.255.85.183:62948ESTABLISHED2449/pythontcp0010.0.24.4:888831.43.185.9:63586ESTABLISHED2449/pythonProto显示连接使用的协议RefCnt表示连接到这个套接字的进程号Types显示套接字的类型State显示socket的当前状态Path表示连接到socket的其他进程使用的路径名参考https://www.linuxcool.com/net...
