Cisco has for some time been using a tool called IOU (IOS on Unix) to be able to simulate configurations for troubleshooting and for testing purposes internally.
Until a while ago this tool was simply a myth and nobody outside of Cisco had been able to get their hands on it.
If you search your regular pirate hideouts I’m sure you will find the tool…
I am still very new to using IOU but already I can see that it is a very attractive platform to lab out scenarios whilst studying.
One limitation at the moment is that the IOU ‘instances’ are only able to have Ethernet or Serial interfaces, whether this will change in future is unknown.
Over the next few days I will get up some more posts on the basic config and some basic queries that a lot of people seem to have judging from the many forum posts I have seen relating to it.
PLEASE NOTE: I do not condone software piracy in any way and if you choose to acquire IOU then you do it at your own risk.