IP addresses serve as one of the primary ways of identifying nodes on the network. Administrators use these logical addresses to place devices on the network in specific segments, control access to the devices via routers and firewalls, and map network devices for client machines.
IP addresses are configured on client systems in two ways:
- Manual assignment. Referred to as static IP addresses, the addresses are manually configured on the device. No typographical errors or duplicates are acceptable.
- Automatic assignment. Referred to as dynamically assigned addresses, the IP settings are leased from a Dynamic Host Configuration Protocol (DHCP) server that holds a pool of available addresses.
Most end-user devices — e.g., desktop computers, laptops, phones, tablets, etc. — are configured as DHCP clients by default. This is an OS setting controlled by administrators. Client systems receive their IP address configurations dynamically because these devices are often transient on the network and frequently move between networks. Because they frequently move, they need different IP configurations depending on location. For example, a laptop in a business office needs one set of network configurations for internet connectivity. But, when that laptop is moved to a coffee shop or home network, it needs a different set of configurations.
While most OSes typically default to DHCP clients, administrators still need to know how to manipulate and troubleshoot these settings, whether on Windows, Linux or macOS.
Windows DHCP client configuration
It may be easiest to discover whether a Windows device is configured as a DHCP client by using the command line.
Windows command line
Open a command prompt or Windows PowerShell console, and then type ipconfig /all. Look for a line in the output that reads DHCP Enabled and a corresponding Yes or No value. Yes means the device is a DHCP client and receives its IP address configuration from a DHCP server. A little further below in the output are the DHCP server’s IP address and info about when the lease was obtained and expired.
Administrators can refresh the DHCP lease by using two simple commands:
PS C:> ipconfig /release
PS C:> ipconfig /renew
The ipconfig /release command clears the current IP address configuration. The ipconfig /renew command causes the client to initiate the four-step DHCP lease generation process. This process provides the …….