모든 서비스 동시 접속자 수

[root@fot etc]# netstat -nap | grep ESTABLISHED | wc -l
11
[root@fot etc]# netstat -nap | grep ESTABLISHED
tcp 0 0 127.0.0.1:52314 127.0.0.1:8009 ESTABLISHED 12237/httpd
tcp 0 0 127.0.0.1:56156 127.0.0.1:8009 ESTABLISHED 12239/httpd
...
tcp 0 0 ::ffff:127.0.0.1:8009 ::ffff:127.0.0.1:52312 ESTABLISHED 12252/java
tcp 0 0 ::ffff:127.0.0.1:8009 ::ffff:127.0.0.1:56156 ESTABLISHED 12252/java
...
tcp 0 0 ::ffff:192.168.1.113:22 ::ffff:192.168.1.200:4722 ESTABLISHED 391/sshd: roora99 [
...

 

웹 동시 접속자 수

[root@fot etc]# netstat -nap | grep :80 | grep ESTABLISHED | wc -l
10
[root@fot etc]# netstat -nap | grep :80 | grep ESTABLISHED
tcp 0 0 127.0.0.1:52314 127.0.0.1:8009 ESTABLISHED 12237/httpd
...
tcp 0 0 ::ffff:127.0.0.1:8009 ::ffff:127.0.0.1:52312 ESTABLISHED 12252/java

nmap으로 열려있는 포트만 확인

nmap -sT -O localhost