External Connector - NAT Mode¶
NAT connectivity can be provided to any connected node in the topology
using the External Connector node (ext-conn). This connection can be
leveraged, for example, to install packages from a Linux repository or
other external public or private package repository.
An IP address is dynamically assigned to the connected node using the next available address from the DHCP pool.
Network |
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Gateway |
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DHCP Pool |
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The router and switch used in the following topology example are not required to leverage NAT mode. They are included only for demonstration and to provide a use case reference.
Use Case |
Provide NAT access to the external network for a Linux server running in a simulation. |
Topology |
IOSv router connecting an IOSv-L2 switch and a Server node connected to an upstream switch and an External Connector node. |
Required Nodes |
External Connector (×1) Server (×1) IOSv (×1) IOSvL2(×1) |
Note
The NAT network is not currently editable. This network is the internal interface of the External Connector and is not exposed to the Workbench. Making the NAT network for the External Connector node configurable via the Workbench is on the CML roadmap and is planned for a future release.
Procedure
Create a new lab in the Dashbaord.
Optional: Give the new lab a name. Example: nat_connector.
Click the nat_connector lab tile to open the Workbench.
Drag-and-drop the required nodes onto the topology canvas.
Connect ext-conn to server, using eth1.
Connect the iosv and iosvl2 nodes to each other using gi0/1.
Connect the server and iosvl2 nodes to each other using eth0
to gi1/0.
Select the ext-conn node.
Click the Edit Config tab in the bottom pane.
Click NAT in the Edit Config pane to select NAT mode.
Press the ESC key to deselect the ext-conn node.
Optional: Click the Design tab in the bottom pane.
Optional: Click Build Initial Bootstrap Configurations in the Design pane.
This action provides a basic configuration and a system-assigned
username and password of cisco/cisco to the Cisco routers in the
lab.
Click the Simulate tab in the bottom pane.
Click Start in the Simulate pane.
The system will start a lab simulation, and the node VMs will start booting.
Wait for all nodes to finish the boot process. Once the server node displays a solid green dot, it is then ready for use. Next, we can verify the NAT connectivity via the External Connector.
Select the server node.
Click the Console tab in the bottom pane.
Click the Open Console button in the Console pane.
Log in.
Use the credentials that you set in the initial configs for the devices. | Username: cisco | Password: cisco
Run the following command to verify connectivity: ifconfig eth1
The command should return an IP address for subnet ``192.168.255.0/24``.
Run the following command to verify connectivity: netstat -nr
The command should return the default gateway IP of ``192.168.255``.