Extract IOSv config from Image file

[ghost]

Sometimes an IOSv device fails to boot and you have to start over. But then you loose your configuration. Before ditching the non-working IOSv device you might try this procedure to recover the configuration.

First determine the location of the image. For that right-click on the faulty device and select "Show in file manager". If the device is running locally a file manager will start in der node directory. But IOSv devices typically run in the GNS3VM. Then you will get a popup like this:

Open a shell in the GNS3VM and then cd (change directory) to the node directory shown. I prefer using a SSH connection, as this allows me to use copy/paste.

Then run the following command:

strings -n 1 hda_disk.qcow2 | sed -n '/^! Last configuration change/,/^end$/p'

If you are lucky the configuration will be shown.

Update: This only works, if the configuration is stored as text. Some IOSv images, mainly switches, store the configuration in a compressed format. Then this simple method will not find the configuration.