Cisco ASA IOS: https://software.cisco.com/download/type.html?mdfid=284143092&flowid=31542
This document describes a problem encountered when you attempt to upgrade the Cisco Adaptive Security Appliance (ASA) to Version 8.4.7 or later or to Version 9.1.3 or later. It also provides the upgrade path that resolves the problem.
When you attempt an ASA upgrade to these versions:
you receive this error message:
No Cfg structure found in downloaded image file
This error message is generated because the file structure for the ASA binary images changed in both Version 8.4.7 and Version 9.1.3. There is a specific upgrade path you must follow.
Follow this version upgrade process:
| Current ASA Image | First Upgrade | Final Upgrade |
|---|---|---|
| 8.2.x | 8.4.6 | 8.4.7 or later, 9.1.3 or later |
| 8.3.x | 8.4.6 | 8.4.7 or later, 9.1.3 or later |
| 8.4.1 through 8.4.4.10 | 8.4.6, 9.0.2 | 8.4.7 or later, 9.1.3 or later |
| 8.5.x | 9.0.2 | 9.1.3 or later |
| 8.6.1 | 9.0.2 | 9.1.3 or later |
| 9.0.1 | 9.0.2 | 9.1.3 or later |
| 9.0.1.1 and later (to include 9.0.2 and later) |
Not Applicable | 9.1.3 or later |
| 9.1.1 | 9.1.2 | 9.1.3 or later |
| 9.1.1.1 and later | Not Applicable | 9.1.3 or later |
Note: If you upgrade to a final version that is later than Version 8.4.7 or Version 9.1.3, the same process applies. Just replace the 8.4.7 or 9.1.3 image in the Final Upgrade column with the final version to which you will upgrade.
原文：http://www.cnblogs.com/syother/p/6872645.html