netstat

$ netstat --helpusage: netstat [-vWeenNcCF] [<Af>] -r         netstat {-V|--version|-h|--help}       netstat [-vWnNcaeol] [<Socket> ...]       netstat { [-vWeenNac] -i | [-cWnNe] -M | -s }        -r, --route              display routing table            显示路由信息，路由表        -i, --interfaces         display interface table        -g, --groups             display multicast group memberships        -s, --statistics         display networking statistics (like SNMP)        -M, --masquerade         display masqueraded connections        -v, --verbose            be verbose        -W, --wide               don't truncate IP addresses        -n, --numeric            don't resolve names            拒绝显示别名，能显示数字的全部转化为数字        --numeric-hosts          don't resolve host names        --numeric-ports          don't resolve port names        --numeric-users          don't resolve user names        -N, --symbolic           resolve hardware names        -e, --extend             display other/more information            显示扩展信息，如uid等等        -p, --programs           display PID/Program name for sockets            显示建立相关连接的程序名        -c, --continuous         continuous listing            每隔一个固定时间执行一次命令        -l, --listening          display listening server sockets            显示处于LISTEN状态的服务        -a, --all, --listening   display all sockets (default: connected)            显示所有选项，默认不显示LISTEN相关        -o, --timers             display timers        -F, --fib                display Forwarding Information Base (default)        -C, --cache              display routing cache instead of FIB  <Socket>={-t|--tcp} {-u|--udp} {-w|--raw} {-x|--unix} --ax25 --ipx --netrom    -t 仅显示tcp相关选项    -u 仅显示udp相关选项  <AF>=Use '-6|-4' or '-A <af>' or '--<af>'; default: inet  List of possible address families (which support routing):    inet (DARPA Internet) inet6 (IPv6) ax25 (AMPR AX.25)     netrom (AMPR NET/ROM) ipx (Novell IPX) ddp (Appletalk DDP)     x25 (CCITT X.25)