In Cisco Packet Tracer, there isn’t a specific "redo" function in configuration mode within the Command Line Interface (CLI). However, you can reapply actions by following these steps:

How to Redo in Configuration Mode in Cisco Packet Tracer 

Steps to Manually Redo in Configuration Mode

1. Undo a Command:

   - In configuration mode, remove a command by prefixing it with `no`. For example, if you set an IP address and need to undo it:

2. Redo the Command:

   - To reapply (redo) the command, simply enter it again:

3. Use Command History:

   - Use the **up arrow** key to scroll through previously entered commands in your CLI. This makes it easy to quickly re-enter commands without typing them again.

 Tips for Efficient Redo Actions in Configuration Mode 

- Save Configurations Frequently: To avoid redoing configurations from scratch, save configurations at key steps.

- Check Syntax: Small typos in the CLI may require you to redo actions, so double-check each command.

 While there is no automatic redo feature in Packet Tracer’s CLI, these steps can help efficiently manage configuration changes.