Netstat This command is commonly used in network monitoring. With this command, you can view the current system listening services and established services, as well as the corresponding ports, protocols and other information.
Netstat parameter description
Netstat parameters, although a lot, but often not much, mainly the following several parameters:
Netstat-[ATUNLP]
- -a:all, indicating all connections, service listening, socket data
- -t:tcp, listing the services of the TCP protocol
- -u:udp, listing the services of the UDP protocol
- -n:port Number, which displays the
- -l:listening with the port numbers, lists the current listening service
- -p:program, List the PID
for the service program
If you need more insight, you can use the man netstat to see a detailed description of the netstat command.
Netstat command test
Netstat-atunlp
Output results such as
Netstat command demo
which
- Proto: Network transport protocol, mainly for TCP and UDP
- Local Address: Ip:port
- Foreign Address: remote host's Ip:port
- State: Connection status, mainly monitored (LISTEN) and established (establised)
- PID: Process number of the service
- Program Name: Service names
The status of the penultimate line above is establised because I am currently using putty to connect to this host.
Source: http://www.01happy.com/linux-netstat-service-listen-port/
From for notes (Wiz)
Use Netstat on Linux to view current service and listening ports