Development of a Network Lab Virtualization

Recently, we installed GNS3 into our computers after uninstalling Dynagen and Dynamips.

What is GNS3?

GNS3 is somewhat similar to Packet Tracer. It provides a GUI for Dynagen and Dynamips. Instead of having to type commands through a notepad, GNS3 is a friendly program that allows you to click and drag routers, computers, switches or servers and create a network topology.

A router’s configuration mode can be accessed by just starting up the router and then selecting Console after right-clicking it. The console, is the same as typing inside the configuration of a router in Packet Tracer, with the exception of the change in a few of the commands.

In order to use a specific router however, you require the IOS of the router in .bin format. Then, you have to add the IOS into the program.

After creating your network topology and configuring it correctly, you can save the file into a .net format file.

Comparing GNS3 to manually creating the .net file, GNS3 is more suited to those that want to practise and have a go at how Dynagen and Dynamips work whereas manually typing the commands on a notepad is more suited to those who have an advanced knowledge on how to work with Dynagen and Dynamips.

Yesterday, we tried to do troubleshooting on the installation of dynamips and dynagen. Apparently, opening the .exe file gave an error. Mr Wagio then asked us to try copying the packet.dll and winpcap.dll files and paste them into the system32 folder. However, it did not work.

I took a look at the readme file and it said to paste the files into the system folder. That too, didn’t work. We thought it was due to the computer’s problem. Mr Wagio then asked us to download the various previous versions of winpcap installers on the website.

In total, I downloaded versions:

3.1-WinPcap
3.2.1-WinPcap
3.1.3-WinPcap
3.1.4-WinPcap
4.0-WinPcap
4.0.1-WinPcap
4.0.2-WinPcap

After uninstalling all the programs, and reinstalling in the order of WinPcap first, followed by the dynagen and dynamips package; and copying and pasting the packet.dll and winpcap.dll files to system32 and system folders, the program still couldn’t work and had the same error.

Today, we decided to install in Aaron’s laptop. And true enough, the first installation was sucessful without errors. We also started to read up on the configuration notes. We learned of things such as autostart. Also learned of how to set the default router model accordingly.

After installing Dynamips on the computer, we tried opening the file.

An error came out:

The procedure entry point PacketGetReadEvent could not be located in the dynamic link library packet.dll.

After a week of reading and researching on Dynamips and Dynagen, we finally managed to download the 2 files.

Apparently, the OS we were using were Debian-Linux. Therefore, in order to install the programs, we needed to have a basic knowledge on shell commands. After a fast and clear tutorial by Mr. Wagio on the few commands, we could install the programs on the other computer on our own. During the process, we learnt of shell commands such as “apt-cache search”, “apt-get install” and how to convert a file into an executable.

However, as we needed to do our reports on Microsoft Word and our slides on Microsoft Powerpoint, we reformatted our computers again to Windows XP Professional. This time, with the usage of a disk that had all the installation files for the drivers.

We managed to install Dynamips and Dynagen within a couple of minutes and will be trying it out tomorrow at the lab again.

We reformatted our computers and installed debian-linux on Wednesday for our project on the Development of Network Lab Virtualization. Aaron tried to install the Windows XP OS on his computer but we found out we had to redownload all of the drivers, which would be a very tiring task as the download speed of the internet in school was slow.

Anyway, back to debian. Debian is a free operating system composed entirely of free and open source software. Debian is somewhat similar to Windows. Web browsers such as Epiphany and Iceweasel are similar to Web Browsers in Windows such as Internet Explorer and Mozilla Firefox.

Next, we tried to download Dynamips and Dynagen from the internet. Apparently, I downloaded the wrong type of file. The files had .rpm and .tar.gz type. Files that had .rpm at the end were for usage in Red Hat while Debian uses .tar.gz to unzip files.

To install dynagen and dynamips, we had to install libpcap, which is used to provide bridging router interfaces to physical network cards.

Then, we need to extract dynagen and dynamips to a suitable location. Then we need to create symlinks, or symbolic links, to dynagen and dynamips executables. A symlink is somewhat like a shortcut to another directory.

It is a cisco router emulater that emulates 1700, 2600, 3600, 3700, and 7200 hardware platforms, and runs standard IOS images. the creator and writer of this emulator, Christophe Fillot, states that this emulator can be used as a training platform for people to be more familiar with cisco devices. It can also be used to check configuration quickly on routers before they are deployed on real routers. This emulator, however, cannot replace real routers and instead can be used as a complementary tool for administrators who want to pass their CCNA/ CCNP/ CCIE exams. Also, the performance of Dynamips is only 1 kpps as compared to the actual 100 kpps of a real router.

Dynamips does not emulate catalyst switches.

Dynagen, a text-based front end program written in Python, uses a “Hypervisor” mode to communicate with Dynamips. This program simplifies building and working with virtual networks.

Dynagen uses a simple configuration file for specifying virtual router hardware configurations.

It also uses simple syntaxes to interconnect routers, bridges, frame-relay and ATM, and Ethernet switches. It doesn’t require any dealing with NETIOS

Dynagen can run in a client / server mode. Simply, Dynagen can run on your workstation and communicate with Dynamips on a back-end server. 

Dynagen can also control multiple Dynamips server simultaneously for distributing large virtual networks across several machines.

Dynagen and Dynamips can also be run on the same system.

Dynagen can support commands such as start router, stop router, reload router, suspend router and telnet to another router.