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GNS3 1.0 Early Release

As many of you know, GNS3 1.0 was released this Monday to all of us early testers who contributed a few months back. Here is my review on getting it setup, and some of the limitations of it thus far!


So finally the long awaited GNS3 1.0 ER has been released to us tester! As you can see from the screenshot above, I was able to get a switch up and working on it!

To get it working, I followed the guide that grossmj wrote on GNS3′s forums http://forum.gns3.net/topic8988.html

1. VMWorkstation, VMPlayer, Oraclebox, or some kind of visualization program
2. ISO of debian-jessie-DI-a1-i386–netinst.iso that you can google for
3. IOU Images for the switches (and routers if you’d like) along with the license file
4. Some Linux CLI experience (or persistence with google searches!)
5. The GNS3 linux files (gns3-gui-master.zip and gns3-server-master.zip)

HOW TO INSTALL (following grossmj’s guide)
1. Install your copy of Debian in your vm

2. Update the software repos by opening up a Terminal window and typing in “apt-get update“. You may need to run as “root” user so “su” to it if it complains that it can’t do it.

3. Place the GNS3 files gns3-gui-master.zip and gns3-server-master.zip and place them on your desktop (or wherever you’d like).

4. Next, let’s install some Python tools (Python2.7 is installed by default but I just followed the guide). Hit “Yes” if prompted.
apt-get install python3
apt-get install python3-setuptools
apt-get install python3-pyqt4
apt-get install python3-ws4py

5. Next up, for the gns3-gui-master.zip file let’s cd to the directory and then type in unzip gns3-gui-master.zip. This will unzip the .zip a folder in the same dir you did the command from. Next, issue a cd gns3-gui-master to enter the folder and we’ll install the files with Python via the command python3 setup.py install

6. Now we’ll install some more Python components …. type in the following commands and hit Yes if prompted.
apt-get install python3-zmq
apt-get install python3-tornado
apt-get install python3-netifaces

7. For the next portion, we’ll unzip the gns3-server-master.zip file. Let’s cd to the directory where the file is (for me its on the desktop) and issue the command unzip gns3-server-master.zip. Now like we did in step 5, we’ll cd inside the unzipped folder contents and install it via python3 setup.py install

8. grossmj mentions that we need to “Fix the missing library for IOU”. Not sure for what but who am I to question one of the GNS3 programmers? In our terminal window issue the command apt-get install libssl1.0.0 and then type in ln -s /usr/lib/i386-linux-gnu/libcrypto.so.1.0.0 /usr/lib/libcrypto.so.4. The latter commands links the two paths together. For more info on links, read this article http://www.cyberciti.biz/faq/creating-soft-link-or-symbolic-link/

9. Now we’ll install the IOUYAP. Download it from http://sourceforge.net/projects/gns-3/f … z/download and as usual place it on your desktop (or wherever but I like the desktop). On our terminal window once downloaded browse to where you put the file (for me the desktop) and issue the command tar zxvf iouyap.tar.gz and then we’ll run a command to copy the ioyap to the /usr/local/bin directory. Run this command to copy it cp iouyap /usr/local/bin/iouyap. For more info on the tar command, lookup http://www.computerhope.com/unix/utar.htm

10. Now this part is the hardest part of install GNS3 1.0 alpha….specifying the IOURC License file. Of course for legal reasons we can’t go in details on how to do this but the GNS3 forum has plenty of help on this! Just like we can’t hand out images for GNS3 0.8.5 I can’t hand these out either. Which leads me to say how is this release of GNS3 not illegal since one needs to….but I digress :) But if you got it I can tell you what you need to do next.

To clean up our terminal window, open up a new terminal window and let’s launch GNS3 by simply typing “gns3″. The GUI should pop up. Enter your GNS3 username GNS3XXXX and email associated with it. Now go to EDIT > PREFERENCES > IOU ON LINUX > and in the first field “Path to IOU” browse to your license file. Note if it isnt in the right format if you click OK and GNS3 doesn’t “accept” it, the window will not close (no error pops up).  If the GNS3 window “accepts” the license key it’ll close and you’ll know it took.

11. Now we’ll also specify the location of that IOUYAP file we had before. Its in the same window where we specified the license file. In GNS3 go to EDIT > PREFERENCES > IOU ON LINUX > and under the “Path to iouyap (local linux server only)” browser to the file. Hit OK.

12. Now similar to what we did for GNS 0.8.5. we need to add the actual images. To specify the images, go to EDIT > PREFERENCES > IOU DEVICES and then click on the “…” on IOU PATH to browse to where you have you IOU images.  Once you do, hit SAVE then OK.

13. One extra step I had to do to install putty on the OS. On our terminal window to install putty type in “apt-get install putty” and then in GNS3 to we’ll need to change app used to console to our IOU devices. In GNS3, go to EDIT > PREF > GENERAL > CONSOLE APPS tab > and on the pulldown window under Preconfigured commands select PUTTY and then hit OK.

14. And your set! Pull out your IOU device and rightclick and hit START. If all goes well, nothing pops up in the console window and the green circle on the right stays green! :) Right click the device and hit Console to open up your session with putty!


Stay tuned for more articles on GNS3 1.0. And I’m sure theres other ways to get this working! Please comment below on the ways you got your GNS3 1.0 working!

William Zambrano

William Zambrano

NYC networkers is run by William Zambrano, a passionate network engineer who has been in the IT industry for eight years who posts up blog articles, YouTube videos, and holds meetup.com events in the NYC area. He lives in Queens, New York and has consulted in various different companies in the NY area. Previously William worked as a Cisco Certified Systems Instructor (CCSI) but now currently works for Arista Networks serving as a Systems Engineer. William can be reached by email at willzambrano@gmail.com

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  1. Thx for the tutorial. Installed it successfully but i see only a black screen in putty.

    • William Zambrano

      Hi Marvin,
      Check the terminal window that you launched GNS3 from — it’ll show any logs if you are getting any errors.

  2. I fixed the problem. I needed a valid license file. I sucessfully created a license with a python scricpt :))
    Thnx again for the great turorial.

    • William Zambrano

      Glad you got it working Marvin! Let me know any bugs or stuff you find would be helpful to post up fixes or common errors for others.

  3. I found an error.I think it has nothing to do with GNS3. When I start an IOU I see the following error messages in my console:

    *Apr 8 20:34:33.366: %AMDP2_FE-6-EXCESSCOLL: Ethernet5/3 TDR=0, TRC=0
    *Apr 8 20:35:52.484: %AMDP2_FE-6-EXCESSCOLL: Ethernet4/0 TDR=0, TRC=0
    *Apr 8 20:36:34.540: %AMDP2_FE-6-EXCESSCOLL: Ethernet3/3 TDR=0, TRC=0
    *Apr 8 20:37:08.610: %AMDP2_FE-6-EXCESSCOLL: Ethernet3/2 TDR=0, TRC=0

    This is what IOU generates. These error messages looks familiar. I have an standalone IOU vmware imagesand generates the same error messages.
    Do you know a solution for this? I never solved it.

    • William Zambrano

      The google searches I’ve done state that this may be a duplex errors which pertains to IOU. Everyone is saying you can ignore the message or change the speed/duplex settings

      • Correct. I read it also.
        I used a config that the messages don’t appear on the console.

        logging discriminator EXCESS severity drops 6 msg-body drops EXCESSCOLL
        logging buffered 50000
        logging console discriminator EXCESS

  4. Nothing appears in console window after starting IOU. Using Putty.

  5. Follow-up to previous post:
    Terminal window output:
    Telnet server ready for connections on
    INFO:gns3.telnet_console:starting telnet console “putty -telnet 4004 -title IOU1 -sl 2500 -fg SALMON1 -bg BLACK”

    • William Zambrano

      brain6, check the IP, notice your seeing telnetting to — try changing it to I telnet I get…

      starting telnet console “putty -telnet 4001 -title IOU -sl 2500 -fg SALMON -bg BLACK”

  6. can any please send the link or send me the new GNS3 1.0 to my email hikmatullah535@yahoo.com


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