GED Reasoning Through Language ArtsReading ComprehensionMedium
A technician is troubleshooting a network issue. The client reports that they cannot access certain websites, but their email and internal company applications are working fine. The technician checks the firewall logs and sees several entries indicating 'DNS resolution failure' for the affected websites. What is the most likely cause of the problem?
- AA physical cable disconnection.
- BA problem with the client's web browser.
- CIncorrect DNS server configuration.
- DAn issue with the local DHCP server.
Show answer & explanationAnswer & explanation
Correct answer: C. Incorrect DNS server configuration.
DNS (Domain Name System) resolution failure means the system cannot translate website names (like google.com) into IP addresses. Since email and internal apps (which might use IP addresses or different DNS settings) are working, but specific websites are not, it points to a problem with how the system is trying to resolve external website names, most likely due to incorrect DNS server configuration.
Why the other options are wrong
- A. A physical cable disconnection would prevent all network access, including email and internal applications.
- B. A web browser issue might prevent browsing, but the firewall logs indicating 'DNS resolution failure' point to a network-level problem before the browser even gets a chance to render content.
- D. A DHCP server issue would likely prevent the client from getting an IP address at all, leading to no network access, not selective website issues.
DNS Resolution
The process by which a hostname (like a website address) is translated into an IP address that computers use to identify each other on a network.
- Essential for accessing websites by name.
- Relies on DNS servers to perform the translation.
- Failure prevents access to resources by hostname.
Memory trick: Check the physical, then the address, then the name, then the application.