Recently one of my vps (CentOS) went down after flushing / clearing iptables rules using below command:
iptables -F
The above command will flush/clear all current firewall rules of your CentOS / Linux server.
Here is how I fixed it. I just restarted iptables rules using below command and my VPS was UP.
service iptables restart
You can also use below command to restart iptables rules.
/etc/init.d/iptables restart
