[root@localhost ~]# ssh root@10.0.0.16
ssh: connect to host 10.0.0.16 port 22: Connection refused
[root@localhost ~]# iptables -I INPUT -p tcp --dport 22 -j ACCEPT
[root@localhost ~]# ssh root@10.0.0.16
ssh: connect to host 10.0.0.16 port 22: Connection refused
[root@localhost ~]# service sshd start
[root@localhost ~]# service sshd restart
Stopping sshd:                                             [  OK  ]
Starting sshd:                                             [  OK  ]
[root@localhost ~]# ssh root@10.0.0.16
ssh: connect to host 10.0.0.16 port 22: Connection refused
[root@localhost ~]# service iptables stop
iptables: Setting chains to policy ACCEPT: filter          [  OK  ]
iptables: Flushing firewall rules:                         [  OK  ]
iptables: Unloading modules:                               [  OK  ]
[root@localhost ~]# ssh root@10.0.0.16
ssh: connect to host 10.0.0.16 port 22: Connection refused
[root@localhost ~]# chkconfig iptables --list
iptables        0:off   1:off   2:on    3:on    4:on    5:on    6:off
[root@localhost ~]# chkconfig iptables off
[root@localhost ~]# chkconfig iptables --list
iptables        0:off   1:off   2:off   3:off   4:off   5:off   6:off
[root@localhost ~]# ssh root@10.0.0.16
ssh: connect to host 10.0.0.16 port 22: Connection refused

[root@localhost ~]# ssh 10.0.0.17
The authenticity of host '10.0.0.17 (10.0.0.17)' can't be established.
RSA key fingerprint is 72:71:eb:f6:b1:4c:48:8c:ec:7a:66:8c:ec:53:0c:6d.
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added '10.0.0.17' (RSA) to the list of known hosts.
root@10.0.0.17's password:
Last login: Fri Jul  3 12:45:20 2015 from 10.0.0.16
[root@localhost ~]#