Partner links

How to install and configure a graphical firewall client in Ubuntu 10.10

gufw16

To create a custom rule, click on the Add button on the main Gufw window. The rule creation window has three tabs – Preconfigured, Simple and Advanced. From the Preconfigured, you can create very broad rules for a preset number of applications and services. The preset services are: FTP, HTTP, IMAP, NFS, POP3, Samba, SMTP, ssh, VNC and Zeroconf, and the preset applications or programs are: Amule, Deluge, KTorrent, Nicotine, qBittorrent, and Transmission.

gufw4

Preconfigured rules

The Simple tab allows you to create rules with a port number defined. This makes it possible to create rules for services and applications not preset in the Preconfigured tab.

gufw5

Gufw's simple rules creation interface

The Advanced tab makes it possible to create more specific rules using source and destinations ports and addresses.

gufw6

Gufw's advanced rules creation interface

The example below creates a rule from the Preconfigured tab allowing ssh traffic into a host. While this makes it easy for anybody to create a firewall rule, it lacks specificity. In this example, ssh traffic from all sources would be allowed in. That’s not a good thing, unless that is what you want.

gufw7

Using pre-configured services

Once a rule has been created, it will be shown in the main window of Gufw. You may also view the rule from a shell terminal by typing sudo ufw status.

gufw8

Generated rules in the main Gufw window

This second example shows how to create a rule from the Simple tab. The example shown in the image below is for a rule allowing ssh traffic in to the host.

gufw9

Creating rules in the Simple tab

Rather than use a service or application name, you could just specify the port number associated with that application or service. To repeat the ssh rule in the example above using a port number, you would specify port 22, which is the default port for ssh.

gufw10

Simple rule creation with port number

This example shows how to create a rule from the Advanced tab. The rule shown in the image below allows ssh traffic from all hosts in a network to a particular host in another network. Note: The IP addresses used in these rules do not represent addresses used in a real case.

gufw11

Advanced rule creation

What if you want to create a rule to allow IPsec VPN traffic. First, you need to know the port numbers involved in an IPsec conversation. These would be port 50 for the Encapsulating Security Payload (esp), and port 51 for the Authentication Header (ah). Thus to create the rule for esp, you would use the port number as shown below.
gufw12

To create a rule for the Authentication Header, you would specify port 51.
gufw13

Share:

Share on facebook
Facebook
Share on twitter
Twitter
Share on pinterest
Pinterest
Share on linkedin
LinkedIn

Partner links

Newsletter: Subscribe for updates

Subscribe
Notify of
guest
0 Comments
Inline Feedbacks
View all comments

Get the latest

On social media

Security distros

Hacker
Linux distros for hacking and pentesting

Crypto mining OS

Bitcoin
Distros for mining bitcoin and other cryptocurrencies

Crypto hardware

MSI GeForce GTX 1070
Installing Nvidia GTX 1070 GPU drivers on Ubuntu

Disk guide

LVM
Beginner's guide to disks & disk partitions in Linux

Bash guide

Bash shell terminal
How to set the PATH variable in Bash
Categories
Archives
0
Hya, what do you think? Please comment.x
()
x