# netstat -anlp |grep LIST |grep sshd
tcp 0 0 127.0.0.1:2222 0.0.0.0:* LISTEN 17571/sshd
tcp 0 0 0.0.0.0:22 0.0.0.0:* LISTEN 17571/sshd
외부에서 접근확인
# ssh -lroot 192.168.30.193 -p 2222
ssh: connect to host 192.168.30.193 port 2222: Connection refused
로컬에서 접근확인
# ssh -lroot 192.168.30.193 -p 22 :: 접근가능
# ssh -lroot 192.168.30.193 -p 2222 :: Listen 주소가 아니기에 접속거부
ssh: connect to host 192.168.30.193 port 2222: Connection refused
# ssh -lroot 127.0.0.1 -p 2222 :: 접근가능
root@127.0.0.1's password:
# ssh -lroot localhost -p 2222 :: 접근가능
root@localhost's password: