Cisco VIRL is powerful network simulation tool. There are weeks when I run simulations 24/7 because of some projects or learning are ongoing. With VIRL you get almost the latest firmware for supported platforms. Almost – sometimes you have to wait for next release for a new firmware to be available. I experienced it a few months ago when with ASA 9.7(1) release Cisco introduced the route-based VPNs (VTIs). At this point VIRL users got the 9.6(2) release bundled into latest simulator release. In other simulation, you may want to use different ASAv firmware versions for various nodes, so your simulation is more similar to your production network.

Cisco VIRL uses real firmware in the simulations. I will show you how you can add different ASAv firmware and use it in parallel with the software available on VIRL repository.

The new ASAv firmware

The first step is to obtain the firmware from cisco.com website. You need to have valid service contract assigned to your CCO profile to do that. I will install 9.8(2) version. The file you need is the qcow2 image – asav982.qcow2

After you get the software login into UWM Administration panel available http://<IP-of-VIRL>/admin and select from the menu Node resources | Images, you can see the list of all uploaded firmware images.

In Cisco VIRL UWM panel you can list all installed firmware images

Click Add button to upload new firmware and select subtype ASAv. Make sure you put hw_vif_model = e1000 in Properties field, specify the version in Release box and leave Name/Version blank. The hw_vif_model definition is the default for the ASAv subtype, but I sometimes experienced communication problems if it is not explicitly defined. When all parameters are specified and firmware image selected from the local drive, you can click Create button. 

Using multiple firmware versions

The new firmware uses the same image name as the existing one – we did it in the previous example by not specifying the Name/Version parameter. That means we superseded the old image with the new one.

Newer firmware image over superseded the older one for same node subtype

The VM Maestro tool is even more misleading in this case. When you add nodes to your topology, you can set the VM Image parameter for each them. If you have multiple images uploaded for a particular node you can see them on the list, and all are active. Unfortunately, no matter what you select VIRL use only the latest, the active image, to boot the device.

If you have multiple images for particular node uploaded you can see all of them on the list but no matter what you choose, only the active one, the latest, will be used.

So is it possible to use multiple firmware versions? Yes, by using the Name/Version parameter. You can modify the parameter for each uploaded image or specify it when you are uploading the new one. I usually just add a version number in this field.

If you want to distinguish images for the same subtype, you can use Name/Version parameter

Now in VM Maestro you can see the new image name available on the list

If you define Name/Version parameter, then new image will be available under new name on the list

The default image for the node remains the 9.7.1 because image name matches the subtype name. However, you can now select different firmware version for selected nodes.