IOU tools are used to manipulate the IOU NVRAM file.
The following tools are available:
The IOU tools are based on Dynamips, see https://github.com/GNS3/dynamips
This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License version 2 as published by the Free Software Foundation.
The full license text is available in the file LICENSE.
Python 2.7 or 3.x is needed. Only standard modules are used.
When iou_import creates a new NVRAM image, it can’t know, which IOU it will use. Therefore on the first saving of the startup-config within IOU you might get the warning “Attempting to overwrite an NVRAM configuration previously written by a different version of the system image.”
You can ignore this warning.
This doesn’t happen, if an existing NVRAM image is updated by iou_import.
iou_import will not compress the startup-configuration.
Therefore if you extract a compressed configuration with iou_export and then re-import it with iou_import, the NVRAM usage will increase. If the flash size is quite small, you might get the error message “NVRAM size too small”.
In this case increase the NVRAM size.