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IOS scripting with Tcl available on almost all platforms

The Tcl scripting (invoked with tclsh command) is now available on almost all IOS-based platforms (apart from the low-end Catalyst switches). For high-end distributed platforms, use the 12.2(33)SRC release, for Catalyst 6500 the 12.2(33)SXH release. On most other platforms, you can use mainstream 12.4 release.
You can find more Tclsh-related information in the Tclsh on Cisco IOS tutorial. Sample Tclsh scripts are available in the Tclsh script library. If you need expert help in planning, developing or deploying Tclsh scripts in your network, contact the author.


  1. Which IOS with TCL for 2501 ? :)
  2. I wrote "almost all", did I not :) There's always Linux for 2500 :D
  3. on the 3560 it's not in IP Base - you need IP Services...
  4. Could I use TCL to quickly update a bunch of interface descriptions?

    I need to block loads of old ports as they shouldn't be used. I currently have an excel macro that produces the config for me ie,

    int s1/1/1
    desc do not use!
    int s1/1/2 etc etc

    Would TCL make this quicker? Any tips on the code as I'm little wary of practicing on the live network!
  5. @Anonymous#2: Sure you can. If this is not something you do on a daily basis, you're probably better off using Excel.

    Also, using an off-line tool to prepare large-scale changes to configuration is probably better than executing a Tcl script on the router.
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