All Entries Tagged With: "Dynamips"
GNS3: OSPF and EIGRP scenario
A ready made GNS3 topology, including 3 interconnected routers in different domains (EIGRP and OSPF) like in the topology below.
Requirements:
- GNS3 or Dynamips install and functional
- Cisco IOS image for 3640 platform with Advanced IP Services
What’s included in the archive:
- routers initial configs
- network diagram
- GNS3 (or Dynamips) config file*
* Check the GNS3 config file for direction
What can you test with this scenario:
- ospf area range command
- ospf summary address command
- advertise loopback interfaces with /24 netmask
- redistribution between OSPF and EIGRP
Load the .net file in GNS3 / Dynamips, apply initial router configuration and you should have working scenario with OSPF and EIGRP routing.
Download
Downloaded times
Popularity: 26% [?]
How to integrate GNS3 with Virtual PC
In this article I want to show you how to extend your posibilities to test a network in GNS3. Sure, it’s simple sometime to use a Loobpack interface on one of your edge routers to simulate an external network, but sometime is useful to have something connected to the router port. Take as an example QoS marking and classification. If you want to mark something inbound, then you need a connection to the router port where you want to mark the packets.
Additional to my example here, which include Virtual PC Simulator, you can find useful tutorial about GNS3 and VMware integration on gns3-labs.com or how to emulate a voice lab with the same tools on blindhog.net.
Even most of you are familiar with GNS3 and maybe Virtual PC Simulator, let me begin with some short description about this 2 software.
GNS3 is a Graphical Network Simulator that allows emulation of complex networks. It allows you to run a Cisco IOS in a virtual environment on your computer (running Linux, MacOS X or Linux). GNS3 is a graphical front end to a product called Dynagen. Dynamips is the core program that allows IOS emulation.
The Virtual PC Simulator (VPCS) allow you to simulate up to 9 PCs. You can ping/traceroute them, or ping/traceroute the other hosts/routers from the virtual PCs when you study the Cisco routers in the Dynamips. VPCS is not the traditional PC, it is just a program running on the Linux or Windows, and only few network commands can be used in it. But VPCS can give you a big hand when you study the Cisco devices in the Dynamips. VPCS can replace the routers or VMware boxes which are used as PCs in the Dynamips network.
Before we start, I assume that you already have these tools installed. If not, please download and install GNS3 and VPCS.
On the following example I will show you how to configure a network topology including 2 Virtual PCs and one router and how to interconnect them in GNS3. This presentation is simulate a basic network, but after you learn how to do it, you can configure more complex one. You can have a look to the topology to understand better what I’m talking about.
Please see the video presentation below:
Popularity: 42% [?]
GNS3: How-to save multiple topology configurations for good
GNS3 is an extremely useful tool if you are using Dynamips to emulate Cisco devices. It is a graphical environment in which even a newbie can do complex configuration by clicking and dragging routers, switches, connections into a topology that can be saved.
The problem that occurred to me in the past (and maybe to you also) is the following. Let’s assume that we create a configuration with routers named R0 and R1 and you save the topology config and also the routers config (“copy run start”). All the files (GNS3 topology config and Dynamips files created for R0 / R1 saved config) will be put into the default GNS3 project directory (e.g. /tmp in Linux or other directory if you are using Windows system). For now it is perfect. You have everything fine.
Next time when you start a topology, by default GNS3 will start with the same routers R0 and R1, and we you boot them, they will load your ex-saved config files, because GNS3 will look for config files into it’s default project directory, and since the name of the routers are the same, it will think that this have to be loaded. So, what you will do when you have 10 topologies that you save. Give all the time different routers name? Even so you will end with a mess in your default GNS3 project directory.
I have a solution for this issue, that you might like. I’m not saying that I have discovered this solution…for sure there is somewhere out there on the Internet, but I think of it by my own and I said that maybe others will use it.
This how-to assume that you know what Dynamips, GNS3 and Linux (any distribution) are. The same steps can be applied on Windows system also. Please check the tutorial by clicking the image below:
*Note: As the file is flash and it’s quite big please have patience until it is loaded*
Popularity: 6% [?]
Dynamips: How to save vlans after switch reload
Most of you already know that in Dynamips after a reload of a switch all the vlans and vtp configurations are gone. There is a way how to save the vlan and vtp configuration even in case of a reload of the switch and I will show you below how to do it. For switch emulator I used a Cisco 3640 IOS image with a NM-16ESW module to have Layer 2 port on the device.
Click below to see the movie and explanation:
How to save vlans after switch reload
Popularity: 4% [?]
