Hosts Manager Script

This Bash script is designed to manage entries in your /etc/hosts file conveniently. It provides options to add, update, append, and remove host entries, as well as wipe all user-added entries while preserving essential default localhost configurations.

Features

• Add New Host: Add a new IP-hostname pair to /etc/hosts with consistent formatting.
• Update Host IP: Update the IP of an existing host entry, retaining associated sub-hostnames.
• Append Sub-hostname: Append additional sub-hostnames to existing IP entries.
• Remove Entry: Remove a specified host entry from /etc/hosts.
• Wipe All User-Added Entries: Remove all entries except default localhost entries, with confirmation steps to prevent accidental deletions.

Installation for Direct Terminal Access

To run the script from any directory, you can move it to /usr/bin:

chmod +x manage-hosts
sudo mv manage-hosts /usr/bin/

Now you can execute the script from anywhere by typing:

manage-hosts

Usage

Run the script to display a menu with available options:

sudo manage-hosts

Menu Options

The script offers the following options:

1. Add New Host

   • Adds a new IP and hostname pair to /etc/hosts.
   • If the IP already exists, it prompts you to use the "Append Sub-hostname" option.

2. Update Existing Host IP

   • Updates the IP address for an existing hostname entry, preserving associated sub-hostnames.
   • Prompts you to choose an entry by number, and then asks for the new IP.

3. Append Sub-hostname

   • Adds a sub-hostname to an existing entry without altering the primary IP or hostname.
   • Prompts you to select an entry by number, then allows you to add sub-hostnames until you return to the main menu.

4. Remove an Entry

   • Removes a specific host entry from /etc/hosts.
   • Prompts you to select an entry by number, then removes it. You can continue removing entries or return to the main menu.

5. Wipe All Non-Localhost Entries

   • Deletes all custom entries in /etc/hosts except for the default entries (e.g., localhost).
   • Provides a confirmation prompt to ensure safe deletion.

Example Workflow

Upon running the script, you’ll see a menu like this:

1. Add new host
2. Update existing host IP
3. Append sub-hostname to an existing entry
4. Remove an existing entry
5. Wipe all non-localhost entries in /etc/hosts (Confirmation required)
Select an option (1-5):

Example usage for updating an IP address:

Select an option (1-5): 2
User-added entries:

1 10.10.11.25 greenhorn.htb
2 10.10.11.23 permx.htb lms.permx.htb

Choose an entry by number to update its IP (or press Enter to return to the main menu): 1
Enter the new IP address: 10.10.11.26
IP address updated for greenhorn.htb.

Color-Coded Output

• Green: Add new host
• Blue: Update host IP
• Yellow: Append sub-hostname
• Red: Remove entry or display errors
• Red Background: Warning for wiping non-localhost entries

Default Entries Preserved

The following default entries are always preserved and restored if missing:

127.0.0.1       localhost
127.0.1.1       kali
::1             localhost ip6-localhost ip6-loopback
ff02::1         ip6-allnodes
ff02::2         ip6-allrouters

These entries are critical for system functionality and are protected from deletion.

Confirmation Process for Wiping Entries

If you select the option to wipe all non-localhost entries, you will be prompted to confirm the deletion. This multi-step confirmation helps safeguard against accidental deletion of entries.

Requirements

• Root Privileges: Modifying /etc/hosts requires root access.
• Bash: This script is compatible with the Bash shell.

Notes

• Color-Coded Output: Each menu option and error message is color-coded for clarity.
• Safety and Preservation: The script prevents the deletion of essential system entries, ensuring safe modifications to your /etc/hosts file.