StudyToCert

All certifications / Network+ / Lessons

CompTIA Network+ N10-009 · Domain 5: Network troubleshooting

Routing issues: routing tables, default routes, address pool exhaustion, incorrect gateway, subnet mask or IP

▶ Watch the overview video

Last reviewed September 25, 2026 · Leer en español

Routing issues show up when hosts can talk locally but not to other networks, or when some destinations work and others do not. Troubleshooting them means checking two places in order: first the host's own IP configuration, because a single wrong value there breaks everything beyond the local subnet, and then the routers' tables, because every router along the path, in both directions, must know where to send the traffic.

Free account

Keep reading for free

Create a free StudyToCert account to read the rest of this lesson: 7 more sections, 7 key terms, a real-world example, an exam tip and self-check questions. Every lesson, lab and practice test is free with an account.

Sign up free Log in

Study Network+ for free
A week-by-week plan with every lesson, quizzes, checkpoint tests, a practice exam and hands-on labs.
Open the Network+ study plan