There are no iptables files in the Linux system/etc/sysconfig directory

In a newly installed Linux system, the firewall is banned by default, and there is no firewall policy configured, and none of the/etc/sysconfig/iptables files exist.

Workaround:

1. Type the following command to create a new file

2. Copy the following code, which opens the 80,3306,22 port by default

# Firewall configuration written by System-config-firewall
# # Manual Customization of this file are not recommended.
*filter
: INPUT ACCEPT [0:0]
: FORWARD ACCEPT [0:0]
: OUTPUT ACCEPT [0:0]
-A input-m state--state established,related-j ACCEPT
-A input-p icmp-j ACCEPT
-A input-i lo-j ACCEPT
-A input-m state--state new-m tcp-p TCP--dport 22-j ACCEPT
-A input-m state--state new-m tcp-p TCP--dport 3306-j ACCEPT
-A input-m state--state new-m tcp-p TCP--dport 21-j ACCEPT
-A input-m state--state new-m tcp-p TCP--dport 80-j ACCEPT
-A input-j REJECT--reject-with icmp-host-prohibited
-A forward-j REJECT--reject-with icmp-host-prohibited
COMMIT

3. Restart the firewall

4. Test, get it done!

There are no iptables files in the Linux system/etc/sysconfig directory