linux 桌面关闭防火墙,Ubuntu关闭防火墙的方法(ufw/iptables)

How do I disable the firewall in Ubuntu Linux server edition? How do I turn off the firewall in Ubuntu Linux version 12.04 or 14.04 LTS server?

The latest version of Ubuntu comes with a program called ufw. It is used for managing a Linux firewall and aims to provide an easy to use interface for the user.

A Note About ufw

As I said earlier, the latest version of Ubuntu comes with ufw (now it is the default firewall configuration tool for Ubuntu). It is developed to ease iptables firewall configuration, ufw provides a user friendly way to create an IPv4 or IPv6 host-based firewall.

List ufw firewall rules, enter:

$ sudo ufw status verbose

Sample outputs:

Status: active

Logging: on (low)

Default: deny (incoming), allow (outgoing), deny (routed)

New profiles: skip

To Action From

-- ------ ----

71.81.22.14 80/tcp ALLOW IN Anywhere

71.81.22.15 80/tcp ALLOW IN Anywhere

To disable ufw based firewall, enter:

$ sudo ufw disable

List current firewall rules and stop firewall (old method)

You can type the following command to see if firewall is active or not (open a terminal or ssh session and type the following command):

$ sudo iptables -L -n

Sample outputs:

Chain INPUT (policy ACCEPT)

target prot opt source destination

ACCEPT udp -- 0.0.0.0/0 0.0.0.0/0 udp dpt:53

ACCEPT tcp -- 0.0.0.0/0 0.0.0.0/0 tcp dpt:53

ACCEPT udp -- 0.0.0.0/0 0.0.0.0/0 udp dpt:67

ACCEPT tcp -- 0.0.0.0/0 0.0.0.0/0 tcp dpt:67

Chain FORWARD (policy ACCEPT)

target prot opt source destination

ACCEPT all -- 0.0.0.0/0 192.168.122.0/24 state RELATED,ESTABLISHED

ACCEPT all -- 192.168.122.0/24 0.0.0.0/0

ACCEPT all -- 0.0.0.0/0 0.0.0.0/0

REJECT all -- 0.0.0.0/0 0.0.0.0/0 reject-with icmp-port-unreachable

REJECT all -- 0.0.0.0/0 0.0.0.0/0 reject-with icmp-port-unreachable

Chain OUTPUT (policy ACCEPT)

target prot opt source destination

You can save existing firewall rules as follows:

$ sudo iptables-save > firewall.rules

Finally, type the following commands to stop firewall and flush all the rules:

$ sudo iptables -X

$ sudo iptables -t nat -F

$ sudo iptables -t nat -X

$ sudo iptables -t mangle -F

$ sudo iptables -t mangle -X

$ sudo iptables -P INPUT ACCEPT

$ sudo iptables -P FORWARD ACCEPT

$ sudo iptables -P OUTPUT ACCEPT

A note about GUI tools for Ubuntu desktop systems

You can also use GUI tool to enable or disable Firewall under Ubuntu Linux desktop edition by visiting System > Administration > Firewall configuration option:

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Fig.01: Disabling Firewall In Ubuntu Linux

Simply unselect “Enabled” option to turn off the firewall.