As I am currently studying for my CCNA, I find it very helpful to be able to practice creating networks in a non-destructive environment. Thus, GNS3 provides that solution. At first it was a little difficult installing it because you simply can’t type in
sudo apt-get install GNS3
That’s not even half of it. So here is how to install GNS3 and have it work efficiently for your CCNA studying needs.
1. First we will install Dynagen and Python-Qt4
sudo apt-get install dynagen python-qt4
2. Download GNS3 and extract in /opt
cd /opt sudo wget http://downloads.sourceforge.net/project/gns-3/GNS3/0.6.1/GNS3-0.6.1-src.tar.bz2?use_mirror=softlayer sudo tar -xjvf GNS3-0.6.1-src.tar.bz2 && rm GNS3-0.6.1-src.tar.bz2 sudo mv GNS3-0.6.1-src /opt/GNS3
3. Create the following directories:
These directories will be used by GNS3 – such as projects – where your working projects will be stored, cache, temp, IOS images, etc.
cd /opt/GNS3 mkdir Dynamips mkdir IOS mkdir Project mkdir Cache mkdir tmp chmod o+rw -R ./Project chmod o+rw -R ./tmp
4. Download binary of dynamips and make it executable
cd Dynamips sudo wget http://www.ipflow.utc.fr/dynamips/dynamips-0.2.8-RC2-x86.bin sudo chmod +x ./dynamips-0.2.8-RC2-x86.bin
You can create a desktop shortcut by right-clicking on the desktop and select “Create Launcher..”, Name it GNS3 and in the command section type in
python "/opt/GNS3/gns3"
Double click to open GNS3 and we will edit the default settings. If you don’t want to use desktop icons you can create a launcher from your programs menu by right clicking on the Main Menu, selecting Edit Menu. Select New Item on the right and you will be presented with the same window where you type in the above. From there you can move the launcher into any menu section of your choice.
5. Go to edit | preferences and in the ‘Terminal command:’ section type in:
gnome-terminal -t %d -e 'telnet %h %p' > /dev/null 2>&1 &
6. Under ‘Paths’ change the ‘Project directory:’ to
/opt/GNS3/Project
and the ‘IOS/PIX directory:’ to
/opt/GNS3/IOS
7. Click on Dynamips tab on the left
For the ‘Executable path:’ type in
/opt/GNS3/Dynamips/dynamips-0.2.8-RC2-x86.bin
8. Change the ‘Working directory:’ to
/opt/GNS3/tmp
Click on the Capture tab on the left
9. For the ‘Working directory for capture files:’ change it to
/opt/GNS3/Project
After you have done all that you will be able to Open and Save your GNS3 projects properly and have an efficient setup for GNS3. In order to use the devices in GNS3 you must obtain our own IOS images from Cisco.
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The best I have ever read on this subject
I hope it will work for me since I am a beginner with Linux need to set GNS3 for my home labb. Can you please write something like this to be able to use VNC remotely
I have been working for a few evenings to get this to work on the Ubuntu with the GNS3 installed through the Add/Remove option under Applications. It just didn't work neither running as sudo gns3 couldn't import any .net labs… did your install script and it still didn't work. So just now before going to bed I completely remove the first install I did and tried the link created on the desktop. and it worked!!! I'm importing the CCIE labs etc.
Two thumbs up to you!! Really great quide.
Thank you very for this!!
AFTER THIS SETTINGS dYNAMIPS IS FAIL TO START
PLEASE GIVE SOLUTION ABOUT IT
Followed the instructions. GNS3 starts. Able to start a router (3640). But when I start a console, it just stops after “Connected to Dynamips VM “R1″ (ID 0, type c3600) – Console port”. The IOS I'm using in Windows, Vista it works. The ios I'm using is c3640-ik9o3s-mz.124-3.bin. Pls help me. I'm stuck. Rgds.
Followed the instructions. GNS3 starts. Able to start a router (3640). But when I start a console, it just stops after “Connected to Dynamips VM “R1″ (ID 0, type c3600) – Console port”. The IOS I'm using in Windows, Vista it works. The ios I'm using is c3640-ik9o3s-mz.124-3.bin. Pls help me. I'm stuck. Rgds.
thanks for the post, it resolve my problem with ubuntu 9.04 and GNS3.
I really loved this post…It made the life so simpler…Thanks a lot!!!
Hi, Can any one tell me that where i can find free Cisco IOS.
Most likely it would be illegal. You can get them from cisco.com
Congratulations!!! I’m from Brazil. I’m begin use GNS3 for Linux. I make your script install. Ok perfect install with ubuntu 10.4. Thanks a lot.
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