Sometimes during the operation of a system, whether it is a home personal computer or a powerful server that serves many connections, it is useful to have a tool at hand that can display data on network activity. Why might this be needed? To control traffic, calculate applications that illegally go online, or users. This is exactly what the utility we are considering is doing.
What is Netstat?
This is an application with which you can find out what is happening at the moment on the web. To start, use the command line. In it, when starting Netstat, additional keys and parameters are used.
, - network statistics, , , , . , , TCP, , .
. . Netstat, :
- -a - TCP, TCP UDP, ;
- -e - Ethernet, , ;
- -n - TCP ;
- -o - , , TCP , , , ;
- -p - , . tcp, udp, tcpv6 udpv6;
- -s - , ;
- -r - IP, route;
- - , ; , ;
- /? - Netstat.
Netstat Windows
, , : «-a | more». , « -a > C:\ ». , , , .
, :
- . .
- . IP- , . 0.0.0.0, 127.0.0.1. .
- . IP , .
- . . . , Listening , «» . Established .
Netstat, -a -b, , . , , .
, :
- closed - , ;
- syn_sent - ;
- syn_received - ;
- close_wait - , .
Netstat Linux
Linux, , Windows. . Netstat :
- , - «netstat -a».
- , TCP - «-at».
- UDP - «-au».
- Netstat - «-l». Listening.
- Netstat TCP - «netstat -lt.
- - «netstat -p».
- - «netstat -s».
, - , Netstat Linux. , :
netstat -ap | grep ssh
, SSH. , , , , :
netstat -an | grep `:80`
Netstat Linux , . : netstat -lnptux. , TCP, UDP, UNIX Socket, .
DoS DDoS
, IP-:
netstat -naltp | grep ESTABLISHED | awk '{print $5}' | awk -F: '{print $1}' | sort -n | uniq -c
IP-:
netstat -na | grep :80 | sort
, :
netstat -np | grep SYN_RECV | wc -l
DoS- , , . . , - .
, , . .
Netstat - . . .
Netstat . . . Netstat . , Linux Netstat SS.