I recently noticed that Cisco has a tool for converting IOS configurations to NX-OS configurations. The tool is called "IOS-NXOS Migration Tool", it is located here: https://tools.cisco.com/nxmt/
My quick review follows.
You need a CCO account to connect to the tool. After you log in, you first make a template which is really a mapping to support the source IOS and the target NX-OS. A limited subset of versions are supported: either Catalyst 6500 12.2SX or Cat 4500 Catalyst 12.2(54)SG to either N7K NX-OS 5.1 or N5K NX-OS 5.0.
After you have a mapping, you upload a configuration file, wait a few seconds, and the tool provides a converted file, as well as a PDF of an exception report with color coding:
- Error Code 1 - Not supported by the tool yet. [Other references suggest you refer to the IOS and NX-OS configuration guide to convert the command manually. You can also view the Cisco IOS commands supported by the tool.]
- Error Code 2 - No equivalent NX-OS command [NX-OS does not support this command and/or feature currently. Other references suuggest looking for alternate ways to achieve this from the existing NX-OS features. Refer to configuration guide again.]
- Error Code 3 - NX-OS command does not support IOS command element [Means that some option of general command not supported) [Other references mention that an attribute of elements of this IOS command not supported in NX-OS currently, Customers are requested to analyze the impact and request potential updates to tool.]
- Error Code 4 - IOS command does not support element [Means the tool's version of IOS does not support command you entered... I found this odd, so my commands came from a working IOS config...]
You also get a .CSV that includes both converted and unconverted commands. For every unconverted command it gives you a summary why.
The reports provides lists two command references:
The tool converts all GE, TenGE, ... interfaces to just Ethernet, and does not try to guess what really fits in a NX-OS chassis or your specific chassis.
My take away - the tool works in general, but some manual clean up will be needed. It does not support more recent NX-OS versions. I probably won't use it, I have scripts and macros already that help me map the old interfaces to supported interfaces.