The tools provided today allow you to view and renew IP addresses. However, you need a solid understanding of IP addressing and subnetting to recognize complex IP addressing issues. The best practice for IP address troubleshooting is to create a network and then have someone create issues for you to solve. You can do this with a real network or a simulated one in Packet Tracer. Either way, just do it. You can further review IP connectivity troubleshooting on pages 71–84 of CCNA Flash Cards and Exam Practice Pack (CCENT Exam 640-822 and CCNA Exams 640-816 and 640-802), Third Edition.