After installing Centos 5.8 I could not pick up any open ports using nmap. So I ran the command #iptables –flush and all started working. However, after about 2 days I could not connect again and had to run the command.
1)How can I permanently ensure that my ports are open
2)What could be causing them to be shut in the first place since I did not touch the iptables?
Configure the firewall to open only the ports that you need to have open. Disabling the firewall entirely is very dangerous. You can use the
system-config-firewall-tui command to configure it from a terminal.
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