네트워크 정상 통신체크 / linux / telnet / nc / curl / dev/tcp

■ 환경

 - linux 환경

 - telnet , nc, curl 등 프로그램 설치된환경

 

■ 목적

 - 출발지에서 목적지까지의 네트워크 통신가능여부 확인용

 

■ 방법

● 목적지 IP : 192.168.0.194

● 목적지 PORT : 9100

구분	통신이 정상적인 상태인 경우	통신이 불가능한 상태인 경우
telnet	[root@linux ~]# telnet 192.168.0.194 9100 Trying 192.168.0.194... Connected to 192.168.0.194. Escape character is '^]'.	[root@linux ~]# telnet 192.168.0.194 9100 Trying 192.168.0.194... 응답없음
nc	[root@linux ~]# nc -zv 192.168.0.194 9100 Ncat: Version 7.50 ( https://nmap.org/ncat ) Ncat: Connected to 192.168.0.194:9100. Ncat: 0 bytes sent, 0 bytes received in 0.02 seconds. [root@linux ~]#	[root@linux ~]# nc -zv 192.168.0.194 9100 Ncat: Version 7.50 ( https://nmap.org/ncat ) 응답없음
curl	[root@linux ~]# curl -v telnet://192.168.0.194:9100/ * About to connect() to 192.168.0.194 port 9100 (#0) * Trying 192.168.0.194... * Connected to 192.168.0.194 (192.168.0.194) port 9100 (#0)	[root@linux ~]# curl -v telnet://192.168.0.194:9100/ * About to connect() to 192.168.0.194 port 9100 (#0) * Trying 192.168.0.194... 응답없음
/dev/tcp	[root@linux ~]# echo > /dev/tcp/192.168.0.194/9100 [root@linux ~]# echo $? 0 [root@linux ~]#	[root@linux ~]# echo > /dev/tcp/192.168.0.194/9100 응답없음