Once you have securely acquired the VMDK image, you can use it across various emulation platforms. Often, you will want to convert the .vmdk file to a .qcow2 file, which is natively optimized for Linux-based QEMU hypervisors used by EVE-NG and GNS3. Converting VMDK to QCOW2 (Optional but Recommended)
Historically, this image was part of Cisco Virtual Internet Routing Lab (VIRL). While CML has replaced VIRL, many older, valid licenses may still provide access to these images through the Cisco Software Download Center. Steps to Download (Official Method):
Version 15.6(2)T is a highly stable "Technology" release. It supports modern features like:
Signifies that the file is Digitally Signed and verified by Cisco, ensuring it has not been modified by unauthorized parties.
Create a directory for the new image under the Cisco vIOS directory path. The folder name must follow EVE-NG naming conventions (e.g., vios-adventerprisek9-m.156-2.t ): mkdir /opt/unetlab/addons/qemu/vios-adventerprisek9-15.6.2T Use code with caution. vios-adventerprisek9-m.vmdk.spa.156-2.t download
Virtual Machine Disk - The format used by VMware and frequently by GNS3 for virtual machine images.
: Ensure you comply with Cisco's licensing terms. Unauthorized use or distribution of their software is against the law.
Summary
The filename itself contains critical information that describes the image's version, features, and intended use: Once you have securely acquired the VMDK image,
The virtual image is a core file used to run a virtualized Cisco IOSv Layer 3 router within network simulation software like GNS3, EVE-NG, or Cisco Modeling Labs (CML). Network engineers and certification candidates widely seek this image because it provides full control-plane routing functionality without requiring expensive, power-hungry hardware routers.
Files downloaded from unofficial sources are often modified. Malicious actors frequently inject backdoors, malware, or cryptominers into these VMDK files. When you boot a compromised virtual router, you could be exposing your entire lab network to espionage.
Once you have legally obtained the image, here’s how to get it running in your preferred network emulator.
: Some IOS features require activation. Ensure you comply with Cisco's licensing terms. While CML has replaced VIRL, many older, valid
mkdir -p /opt/unetlab/addons/qemu/vios-adventerprisek9-m.SPA.156-2.T/ Use code with caution.
Because it is optimized purely for x86 computer architectures, the resource requirement for each running node is remarkably small compared to newer container-based routing engines: Technical Metric Minimum Required Value vCPU allocation Disk Interface VirtIO or IDE Underlying Hardware Acceleration KVM Enabled (via nested virtualization) Deploying the Image Across Mainline Emulators
vios-adventerprisek9-m.vmdk.spa.156-2.t Cisco IOSv image (Layer 3 Virtual IOS) typically used for network simulation in environments like Cisco Modeling Labs (CML) Official Download Method
To download the VIOS-ADVENTERPRISEK9-M.VMDK.SPA.156-2.T software image, follow these steps: