In the previous article, you should be able to run a router on GNS3.
In this article, I'll write down some steps to make a topology on GNS3 to make your CCIE preparation easier.
1. Add HWIC
Before you build a network topology, you should add the HWIC on your Router. Since C3600 series have no routed interface on it, otherwise, you will not be able to connect any other routers.
For adding HWIC, double-click the router icon, and bring yourself into Node configurator.
In the Node configurator, select R1, then select Slots tab.
In the Slots, you will see slot 0... your choice of these slots are something like below.
I chose NM-1FE-TX this time, it is because there is no other routed FastEthernet option for C3600. You may choose NM-4E, which support 4 Ethernet interface at one slot, but it only supports for Ethernet interface, not FastEthernet.
2. Inter-Router Connection
To connect each rotuer interfaces, use RJ-45 lookalike icon which is located at left side of the window.
With your click of the RJ-45 icon, the icon turns something like above and it means you may locate virtual physical inter router connection.
To actually locate the physical cable, just click the router and choose the interface whichever you wish to connect from.
Then, bring your mouse pointer to other router and click on it. You may see the set of interfaces as you saw in the previous router.
3. Save Project as...
You may save a project as it does in other programs. Project means a the set of files of topology, nvram, configurations, and captures.
Press Command + S to overwrite the project, you might want to use save project as, go to file menu and select it.
When you save the project, I recommend you to check all the radio box. In this mode, your working logs will all automatically saved and which means it works at review moment.
You will see the files like above, after you save the project.
Also you will see topology.png in it, that is a topology picture you created, is automatically saved.
The topology.net is a something like a configuration of a Cisco router for GNS3. You can open this file with a text editor, and will see some settings inside the topology.net file.
Next article, I will write about this topology.net file and you will understand how you tune the GNS3 more stable and lower CPU usage.
