Hands-On Lab: Verifying IP Parameters on Linux (GUI and CLI)

This hands-on lab covers checking a Linux machine's current IP configuration using both the GUI network settings panel and command-line tools, and demonstrates renewing a DHCP lease using standard Linux networking utilities.

Linux IP Configurationip addr CommandDHCP Client Utilities

~2 min read · Updated Sep 12, 2026

Lab Objective

Determine a Linux machine's current IP address, subnet mask, default gateway, and DNS servers using both the GUI network settings and command-line tools, then renew its DHCP lease.

Lab Purpose

Linux systems are common in server rooms, data centers, and among many engineers' own workstations, and the modern ip command family has largely replaced the older ifconfig utility on most current distributions — familiarity with both the current and legacy tools helps when working across systems of different ages.

Lab Topology

Linux Machine ---- connected to a switch port
                   configured for DHCP (client)

Task 1: Check IP Configuration via the GUI

Open the desktop environment's network settings panel and view the active connection's IPv4 details.

Task 2: Check IP Configuration via the Command Line

Use the modern ip command to display the current address and interface state.

Task 3: Check the Default Gateway and DNS Configuration

Use appropriate commands to display the default route and the DNS servers currently configured.

Task 4: Renew the DHCP Lease

Use the appropriate DHCP client utility to release and renew the current lease.

Solution and Verification

GUI Method (GNOME example):
Settings > Network > click the gear icon next
to the active connection > IPv4 tab

  Address: 192.168.1.72
  Netmask: 255.255.255.0
  Gateway: 192.168.1.1

$ ip addr show

2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP>
    inet 192.168.1.72/24 brd 192.168.1.255 scope global eth0

$ ip route show

default via 192.168.1.1 dev eth0

$ cat /etc/resolv.conf

nameserver 8.8.8.8
nameserver 8.8.4.4

$ sudo dhclient -r eth0
$ sudo dhclient eth0

$ ip addr show eth0 | grep inet

    inet 192.168.1.79/24 brd 192.168.1.255 scope global eth0
    -- Address changed slightly (.72 to .79),
    -- the same normal DHCP behavior seen
    -- earlier in the Windows lab

Key Takeaway

The ip addr, ip route, and /etc/resolv.conf combination on Linux provides the same three pieces of information — address/mask, gateway, and DNS — that a single ipconfig /all command provides on Windows, just split across a few dedicated commands rather than one consolidated view.

Written & researched by Dr. Shahin Siami

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