GNS3 is a continuously developed network emulator program. And those who prepare for the Cisco exams are more likely to use the GNS3 program. The biggest advantage of using this software is that it is free. Furthermore, many detailed network designs can be designed and run on it.
Many people had problems with using Cisco Switch on GNS3. With the Appliance structure, it is now easier to install and use the network device.
In order to use Cisco IOU images in GNS3 program, GNS3 VM Server must be installed. Otherwise, you will not be able to install the IOU.
In order to use Layer 2 Switch, you need to download the necessary IOS image and import it with this application. You can find the IOU L2 Appliance installation file at the end of the article.
To import the IOU image, follow the steps below.
After you download the Cisco IOU L2.gns3a file to your computer, double-click it.
After opening the program, you will be informed about the IOU L2 installation. You can see that Layer 2 Switch is in Multilayer Switch category.
To import GNS3 Appliance, click Next.
Select GNS3 VM Server for installation and click Next.
The files required for the IOU are as follows. You can update the files to be downloaded by pressing the Refresh button. Select the existing Cisco IOU L2 15.2.d file (i86bi-linux-l2-adventerprisek9-15.2d.bin) and check if the GNS3 VM Server is running before clicking Next.
GNS3 VM Server is currently running in the background.
You must have the L2 image in the Required Files window. The distribution of these images is strictly prohibited and you can do research on the Internet to download them.
After downloading the IOU image, click Next to load the selected image.
Do you want to install version 15.2d? Continue by clicking Yes.
The hardware specifications for the Appliance that will run on the GNS3 VM are as follows.
When importing, the new device is reported to be in the Multilayer Switch category.
After you have successfully completed the IOU installation, click OK.
Create a new project in GNS3 to check the added image.
As you can see in the image below, Layer 2 Switch with 15.2d image is available in the tools menu. Drag and drop the switch into the workspace.
At the CLI prompt, execute the show version command and check the system image and installation location of the Layer 2 Switch.
As you can see, the L2 Appliance has installed successfully!
You can check the interfaces of the switch by running the show ip interface brief command on the switch.
Create a new VLAN to verify the functionality of the IOU image and run the do show vlan command in config mode to verify the VLAN configuration.
Cisco IOS Software, Linux Software (I86BI_LINUXL2-ADVIPSERVICESK9-M), Version 15.2(CML_NIGHTLY_20151103)FLO_DSGS7, EARLY DEPLOYMENT DEVELOPMENT BUILD, synced to FLO_DSGS7_POSTCOLLAPSE_TEAM_TRACK_DSGS_PI5
Technical Support: https://www.cisco.com/techsupport
Copyright (c) 1986-2015 by Cisco Systems, Inc.
Compiled Wed 04-Nov-15 02:31 by mmen
ROM: Bootstrap program is Linux
IOU1 uptime is 2 minutes
System returned to ROM by reload at 0
System image file is "unix:/opt/gns3/images/IOU/i86bi-linux-l2-adventerprisek9-15.2d.bin"
Last reload reason: Unknown reason
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Linux Unix (Intel-x86) processor with 158154K bytes of memory.
Processor board ID 2048001
16 Ethernet interfaces
1 Virtual Ethernet interface
16K bytes of NVRAM.
Configuration register is 0x0