ipconfig - macOS

Overview

The ipconfig command in macOS is used to configure and display network interface parameters. It allows for viewing configuration settings and refreshing Dynamic Host Configuration Protocol (DHCP) and DNS settings. This command is crucial for network administration, troubleshooting connectivity issues, and scripting network configurations.

Syntax

The general syntax for the ipconfig command is as follows:

ipconfig <command> <option>

Where <command> is the action you want to perform and <option> depends on the command used.

Options/Flags

Here is a breakdown of the most commonly used options/flags in ipconfig:

  • set: This command sets the specified interface to use the specified configuration.
  • get: Retrieves and displays specific network information.
    • ipconfig getifaddr <interface>: Gets the IP address of the specified interface.
    • ipconfig getpacket <interface>: Shows DHCP packet information received by the specified interface.
    • ipconfig getv6packet <interface>: Shows DHCPv6 packet information received by the specified interface.
  • renew: Renews DHCP lease, obtaining a new IP address.
    • ipconfig renew <interface>: Renews DHCP lease for a specified interface.
  • release: Releases the DHCP lease, dropping the IP address.
    • ipconfig release <interface>: Releases DHCP lease for a specified interface.

Examples

1. Getting the IP address for en0:

ipconfig getifaddr en0

2. Renewing DHCP lease for en0:

ipconfig renew en0

3. Releasing DHCP lease for en0:

ipconfig release en0

4. Viewing DHCP packet info:

ipconfig getpacket en0

Common Issues

  • Permission Issues: Running ipconfig without sufficient privileges results in errors. Use sudo to execute commands that modify network configurations.
  • Interface Not Found: Ensure the interface name (like en0, en1) is correct. Misnamed interfaces will lead to “interface not found” errors.
  • DHCP Lease Not Obtained: Sometimes, DHCP settings might not be available or the network might have restrictions causing the command to fail in obtaining/releasing a lease.

Integration

ipconfig can be integrated with other commands for scripts or troubleshooting, for example:

#!/bin/bash
# Check if your Mac can obtain a new DHCP lease
ipconfig set en0 DHCP
NEW_IP=$(ipconfig getifaddr en0)
echo "New IP address is $NEW_IP"
  • ifconfig: Used to configure or query network interface parameters.
  • networksetup: A tool for configuring network settings primarily used in GUI environments.
  • ping: Useful for checking the reachability of a host on an IP network.

For further reading and more detailed description, visit the Apple Developer Documentation.