서비스 중인 포트 사용 확인
# netstat -nlp
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address Foreign Address State PID/Program name
tcp 0 0 0.0.0.0:3306 0.0.0.0:* LISTEN 2290/mysqld
tcp 0 0 0.0.0.0:21 0.0.0.0:* LISTEN 2114/vsftpd
tcp 0 0 0.0.0.0:22 0.0.0.0:* LISTEN 2098/sshd
tcp 0 0 :::22 :::* LISTEN 2098/sshd
Active UNIX domain sockets (only servers)
Proto RefCnt Flags Type State I-Node PID/Program name Path
unix 2 [ ACC ] STREAM LISTENING 5582 2367/gam_server @/tmp/fam-root-
unix 2 [ ACC ] STREAM LISTENING 5393 2290/mysqld /var/lib/mysql/mysql.sock