[simon@simon-Dell-Precision-M3800 ~]$ su
Password:
su: Authentication failure
[simon@simon-Dell-Precision-M3800 ~]$ su
Password:
[root@simon-Dell-Precision-M3800 simon]# iptables --list
Chain INPUT (policy ACCEPT)
target     prot opt source               destination

Chain FORWARD (policy ACCEPT)
target     prot opt source               destination

Chain OUTPUT (policy ACCEPT)
target     prot opt source               destination
[root@simon-Dell-Precision-M3800 simon]#