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Article Directory
A, Netstat
Netstat is a command-line tool can be used on all of the listed network socket connection system, comprising tcp, udp and unix socket, while it also listed in the listening state (i.e., waiting for access requests) socket.
Listening port (list all ports, to see whether the service is running)
$ netstat -lntp # 查看系统的监听端口(最常用)
Two, Netstat commonly used commands
$ netstat -a # 列出所有连接
$ netstat -at # 列出 TCP协议的连接
$ netstat -au # 列出 UDP 协议的连接
$ netstat -ant # 禁用反向域名解析，加快查询速度(列出所有 TCP 协议的连接，禁用域名解析技术)
$ sudo netstat -nlpt # 获取进程名、进程号
$ sudo netstat -ltpe # 获取进程名、进程号以及用户 ID
$ netstat -s # netstat 可以打印出网络统计数据，包括某个协议下的收发包数量。
$ netstat -rn # 显示内核路由信息
$ netstat -i # 打印网络接口
$ netstat -ct # 持续输出
$ netstat -g # 输出 IPv4 和 IPv6 的多播组信息。
Viewer 2.1 Linux port usage
netstat –apn //查看所有的进程和端口使用情况
netstat -ntlp //查看当前所有tcp端口·
netstat -ntulp |grep 80 //查看所有80端口使用情况, kill -9 {PID}
netstat -an | grep 3306 //查看所有3306端口使用情况·
# 打印 active 状态的连接，使用watch 命令监视 active 状态的连接
$ netstat -atnp | grep ESTA
$ watch -d -n0 "netstat -atnp | grep ESTA"
# 查看服务是否在运行（指定服务名）
$ sudo netstat -aple | grep ntp
udp 0 0 enlightened.local:ntp *:* root 17430 1789/ntpd
udp 0 0 localhost:ntp *:* root 17429 1789/ntpd
udp 0 0 *:ntp *:* root 17422 1789/ntpd
udp6 0 0 fe80::216:36ff:fef8:ntp [::]:* root 17432 1789/ntpd
udp6 0 0 ip6-localhost:ntp [::]:* root 17431 1789/ntpd
udp6 0 0 [::]:ntp [::]:* root 17423 1789/ntpd
Viewer 2.2 Linux port occupancy
ps -aux | grep tomcat # 查看特定进程和端口使用情况
ps -aux | grep java # `ps -aux | grep pid`同效
netstat -nat | grep -iw "8080" | wc -l # 查看8080端口被占用的数量
netstat -nat | grep -iw "8080" # 当前8080端口被哪些进程占用
lsof -i:8080 # 查看8080端口PID、FD、USER等信息
About kill the process, please click: https: //blog.csdn.net/wsp_1138886114/article/details/98207128
Three, Netstat command details
Command:netstat -a , -tlists the TCP protocol, -ulists the UDP protocol
$ netstat -a # 列出所有连接
Active Internet connections (servers and established)
Proto Recv-Q Send-Q Local Address Foreign Address State
tcp 0 0 enlightened:domain *:* LISTEN
tcp 0 0 localhost:ipp *:* LISTEN
tcp 0 0 enlightened.local:54750 li240-5.members.li:http ESTABLISHED
tcp6 0 0 ip6-localhost:ipp [::]:* LISTEN
udp 0 0 enlightened:domain *:*
udp 0 0 *:bootpc *:*
udp6 0 0 [::]:54952 [::]:*
Active UNIX domain sockets (servers and established)
Proto RefCnt Flags Type State I-Node Path
unix 2 [ ACC ] STREAM LISTENING 12403 @/tmp/dbus-IDgfj3UGXX
unix 2 [ ACC ] STREAM LISTENING 40202 @/dbus-vfs-daemon/socket-6nUC6CCx
$ netstat -at # 列出 TCP协议的连接
Active Internet connections (servers and established)
Proto Recv-Q Send-Q Local Address Foreign Address State
tcp 0 0 enlightened:domain *:* LISTEN
tcp 0 0 localhost:ipp *:* LISTEN
tcp 0 0 enlightened.local:37892 ABTS-North-Static-:http ESTABLISHED
.....
$ netstat -au # 列出 UDP 协议的连接
Active Internet connections (servers and established)
Proto Recv-Q Send-Q Local Address Foreign Address State
udp 0 0 *:34660 *:*
udp 0 0 enlightened:domain *:*
udp 0 0 *:ntp *:*
udp6 0 0 fe80::216:36ff:fef8:ntp [::]:*
udp6 0 0 ip6-localhost:ntp [::]:*
udp6 0 0 [::]:ntp [::]:*
$ netstat -ant # 列出所有 TCP 协议的连接，没有使用域名解析技术
Active Internet connections (servers and established)
Proto Recv-Q Send-Q Local Address Foreign Address State
tcp 0 0 127.0.1.1:53 0.0.0.0:* LISTEN
tcp 0 0 127.0.0.1:631 0.0.0.0:* LISTEN
tcp 0 0 192.168.1.2:49058 173.255.230.5:80 ESTABLISHED
tcp 0 0 192.168.1.2:33324 173.194.36.117:443 ESTABLISHED
tcp6 0 0 ::1:631 :::* LISTEN
-l: Displays only listening sockets (sockets is the so-called enabling applications to read and write and send and receive communication protocols (protocol) program and data)
-p: display the process identifier and program name, and each socket / port belongs to a program.
-n: DNS polling is not performed, display IP (speed up operation)
$ sudo netstat -nlpt # 获取进程名、进程号以及用户 ID
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address Foreign Address State PID/Program name
tcp 0 0 127.0.1.1:53 0.0.0.0:* LISTEN 1144/dnsmasq
tcp 0 0 127.0.0.1:631 0.0.0.0:* LISTEN 661/cupsd
tcp6 0 0 ::1:631 :::* LISTEN 661/cupsd
$ sudo netstat -ltpe # 同时查看进程名、进程号和用户名。
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address Foreign Address State User Inode PID/Program name
tcp 0 0 enlightened:domain *:* LISTEN root 11090 1144/dnsmasq
tcp 0 0 localhost:ipp *:* LISTEN root 9755 661/cupsd
tcp6 0 0 ip6-localhost:ipp [::]:* LISTEN root 9754 661/cupsd
$ netstat -s # netstat 可以打印出网络统计数据，包括某个协议下的收发包数量。
Ip:
32797 total packets received
0 forwarded
0 incoming packets discarded
32795 incoming packets delivered
29115 requests sent out
60 outgoing packets dropped
Icmp:
125 ICMP messages received
0 input ICMP message failed.
ICMP input histogram:
destination unreachable: 125
125 ICMP messages sent
0 ICMP messages failed
ICMP output histogram:
destination unreachable: 125
... OUTPUT TRUNCATED ...
$ netstat -rn # 显示内核路由信息
Kernel IP routing table
Destination Gateway Genmask Flags MSS Window irtt Iface
0.0.0.0 192.168.1.1 0.0.0.0 UG 0 0 0 eth0
192.168.1.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0
$ netstat -i # 打印网络接口
Kernel Interface table
Iface MTU Met RX-OK RX-ERR RX-DRP RX-OVR TX-OK TX-ERR TX-DRP TX-OVR Flg
eth0 1500 0 31611 0 0 0 27503 0 0 0 BMRU
lo 65536 0 2913 0 0 0 2913 0 0 0 LRU
$ netstat -ie/ifconfig
Kernel Interface table
eth0 Link encap:Ethernet HWaddr 00:16:36:f8:b2:64
inet addr:192.168.1.2 Bcast:192.168.1.255 Mask:255.255.255.0
inet6 addr: fe80::216:36ff:fef8:b264/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:31682 errors:0 dropped:0 overruns:0 frame:0
TX packets:27573 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:29637117 (29.6 MB) TX bytes:4590583 (4.5 MB)
Interrupt:18 Memory:da000000-da020000
lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:65536 Metric:1
RX packets:2921 errors:0 dropped:0 overruns:0 frame:0
TX packets:2921 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:305297 (305.2 KB) TX bytes:305297 (305.2 KB)
$ netstat -ct # 持续输出
$ netstat -g # 输出 IPv4 和 IPv6 的多播组信息。
IPv6/IPv4 Group Memberships
Interface RefCnt Group
--------------- ------ ---------------------
lo 1 all-systems.mcast.net
eth0 1 224.0.0.251
eth0 1 all-systems.mcast.net
lo 1 ip6-allnodes
lo 1 ff01::1
eth0 1 ff02::fb
eth0 1 ff02::1:fff8:b264
eth0 1 ip6-allnodes
eth0 1 ff01::1
wlan0 1 ip6-allnodes
wlan0 1 ff01::1