GNS3 Quick Start Guide for Linux Users

Let’s start our focus to Linux users now Our examples will use Ubuntu  Anyone can download Ubuntu from

www.ubuntu.com for free – it just may take awhile since it’s a large file. Performance is somewhat better in a Linux environment, but the difference is not significant. First, we’ll install necessary dependencies 

Step 1: Install necessary dependencies

Open the Synaptic Package Manager.

Go to the System menu, then

Administration, and finally Synaptic

Package Manager.

Click the Search button in the toolbar,

type python-qt4 in the Search box and

click the Search button. 

When you find python-qt4, click on the

white box in front of it, and choose Mark

for Installation. 

Click Mark and the click the Apply button in the toolbar.

On the Summary window, click Apply.

Step 2: Download GNS3.

Use Firefox to access http://www.gns3.net.  

Click on the green Download button.

You may choose any of the source

archives for Linux. We will use GNS3-0.5-

src.tar.gz. 

Click on Mirror 1 or Mirror 2 to begin the

download.

By default, the file will be downloaded

to the desktop.

Next, right-click on the file on the desktop, GNS3-0.5-

scr.tar.gz, and choose Extract Here. 

You’ll see a new icon on the desktop labeled

GNS3-0.5-src.

Now we need to download the latest Dynamips binary for

Linux. Use Firefox to visit the Dynamips blog Web site at:

www.ipflow.utc.fr/blog/

In our example, it is found farther down the page as 0.2.8-

RC2 binary for Linux x86 platform.

Drag the downloaded file, dynamips-0.2.8-RC2-

x86.bin into the GNS3-0.5-src folder. 

Let’s change the Dynamips permissions to allow

execution. Double-click on dynamips-0.2.8-RC2-

x86.bin and choose Properties. 

Click on the Permissions tab, and then click the box next to Execute: Allow

executing file as program. Then click Close.

Step 3: Configuring GNS3

Double-click the gns3 icon to start the application. Click the Run

button. 

The Setup Wizard begins with a message as shown. 

Click on the big number 1 to open the Preferences window

(actually located under the Edit menu in GNS3). 

Then click Dynamips in the left-hand pane.

Click the ellipses next to Executable path and then 

click dynamips-0.2.8-RC2-x86.bin and followed by 

the Open button. 

When you return to the Preferences screen, click

OK.

Now you return to the Setup Wizard. Click the big number 2 to

open the IOS images and hypervisors window (actually located

under the Edit menu in GNS3). 

Use the ellipses button next to the Image file box

to locate an IOS image. 

As mentioned earlier, you must provide your own

Cisco IOS to use with GNS3 due to licensing issues.

GNS3 is meant to be used in a lab environment

for testing and learning. Once you have obtained

your own copy of a Cisco IOS for one of the

supported platforms, you are ready to continue.

Current platforms supported include:

1710                                                        2611

2691

1720

1721

1750

1751

1760

2610

2610XM

2611XM

2620

2620XM

2621

2621XM

2650XM

2651XM

3620

3640

3660

3725

3745

7200

Then click the Save button followed by the Close button You’ll return again to the Setup Wizard window Click OK to

finish. 

It’s time now to create our first simple topology. So whether you are Windows user or a Linux user, continue to the next

.