Cisco CCNA (200-301)Network FundamentalsEasy
A network engineer is troubleshooting a client workstation that can ping other devices on its local subnet but cannot reach resources on other subnets, including the internet. The client's IP address, subnet mask, and DNS server settings are all confirmed to be correct. What is the most likely misconfiguration on the client workstation?
- AIncorrect DHCP server address
- BIncorrect default gateway address
- CIncorrect VLAN assignment
- DIncorrect MAC address
Show answer & explanationAnswer & explanation
Correct answer: B. Incorrect default gateway address
If a client can communicate within its local subnet but not beyond it, the issue almost always points to an incorrect or missing default gateway. The default gateway is the IP address of the router on the local subnet that traffic is sent to when destined for another network.
Why the other options are wrong
- A. An incorrect DHCP server address would prevent the client from obtaining any IP configuration, which is not the case here.
- C. Incorrect VLAN assignment would likely prevent even local subnet communication or place it in a completely wrong network.
- D. An incorrect MAC address would prevent any Layer 2 communication, making even local pings impossible.
Default Gateway Function
The default gateway is the IP address of the router interface on the local subnet that hosts send traffic to when the destination is outside their local network.
- Crucial for inter-subnet communication and internet access.
- If misconfigured, a host can only communicate with devices on its immediate local network.
- Typically configured manually or assigned by DHCP.
Memory trick: Local is Fine but Global is Blocked? Gateway is Gone!