GNS3 Integration

The GNS3 guide is designed to help users leverage Indeni as they learn how to create networks and map topologies for large scale deployment, or for simply testing and learning in your home lab. Not only can you understand if your network topology is correct in a virtualized environment, but you can now get in front of potential configuration issues while also gaining valuable insight into industry best practices.

SUPPORT & REQUIREMENTS

Support for GNS3

This process has been tested with the CISCO 7200 IOS v.12, v.15, and v.16. While other dynamips-based IOS images may work, we cannot guarantee the same results across the wide variety of IOS devices. If you encounter issues please join the Indeni Community so others can assist, test, and help remediate. We highly encourage collaborative testing!

Requirements

You have downloaded and deployed the Indeni server. If you have not already deployed the Indeni server, please be sure to review the device requirements and installation instructions.
You have installed GNS3 and added at least one supported Cisco device running a supported version of Cisco IOS.
The Indeni server has network connectivity to the GNS3 device(s) you want to monitor. For example, the Indeni Server can access, via the SSH protocol (version 2), the devices hosted in the GNS3 environment. This requires that SSH v2 is enabled on the target Cisco device(s), and users are configured with privilege level 15 access.

CONNECTION & CONFIGURATION

There are many ways to network Indeni and GNS3 together. The following image shows a basic topology using the GNS3_VM. Please note that eth0, in the GNS3_VM, is bridged into the local LAN, with the Indeni server (not shown here) is bridged into the same LAN. This puts the Indeni server and the Cisco device (R1) on the same network, which is how Indeni can interrogate and monitor the Cisco device.

Configuring the Cisco Device in GNS3

Your GNS3-based device will need some basic configuration to allow Indeni to interrogate and monitor it, so here’s what you’ll need to know:

Cisco IOS Commands

Please Note: The following is provided as a “quick start” to configuring your IOS device. For a more detailed explanation, see https://www.cisco.com/c/en/us/td/docs/ios/12_2/security/configuration/guide/fsecur_c/scfssh.html

You can run these commands to configure your device. In general, the steps are:

Enter configuration mode
Set the hostname
Configure the device network interface
Set the domain-name
Add a user with EXEC privilege — required for Indeni
Setup the SSH server
Configure the terminal access for the local user:


R2>enable
R2#configure terminal
R2(config)#hostname R2
R2(config)#interface f0/0
R2(config-if)#ip address dhcp
R2(config-if)#no shutdown
R2(config-if)#exit
R2(config)#ip domain-name example.com
R2(config)#username indeni privilege 15 secret 0 indeni4it
R2(config)#crypto key generate rsa modulus 1024
R2(config)#ip ssh version 2
R2(config)#line vty 0 4
R2(config-line)#login local
R2(config-line)#transport input ssh
R2(config-line)#end
R2#write mem

Before trying to add the device to Indeni there are a few tests you can perform to make sure the device is ready:

Ping your GNS3-based device from the Indeni server to make sure it is reachable.
SSH into your GNS3-based device. For example, ssh -2 -l <cisco-username> <device-IP>.

SSH will prompt you for the password configured for the user. Once you have successfully SSH’d into your device with the above command, you can add the device to Indeni for monitoring and remediation suggestions.