查看端口占用情况
lsof -i:端口号
比如：
lsof -i:8081
输出如下：
COMMAND PID USER FD TYPE DEVICE SIZE/OFF NODE NAME
node 44195 mac 20u IPv6 0xc2056b16e4568339 0t0 TCP *:sunproxyadmin (LISTEN)
node 44195 mac 28u IPv6 0xc2056b16e456ab79 0t0 TCP localhost:sunproxyadmin->localhost:56335 (ESTABLISHED)
ReactNati 45104 mac 8u IPv6 0xc2056b16e456a5b9 0t0 TCP localhost:56335->localhost:sunproxyadmin (ESTABLISHED)
ReactNati 45104 mac 12u IPv6 0xc2056b16e456a5b9 0t0 TCP localhost:56335->localhost:sunproxyadmin (ESTABLISHED)
关闭端口
kill -9 44195
kill -9 45104
执行上门两条命令，