Explain why a successful DNS lookup for `webserver.acme.local` does not prove that a device at `10.10.10.30` is online.
Answer
A DNS lookup verifies that DNS contains and returns the name-to-address mapping. It does not test whether a device is configured with that address, powered on, reachable, or responding to application traffic. The lab explicitly states that the listed addresses are not assigned to devices and that the exercise tests DNS records only.
Explanation
DNS resolution and host reachability are separate tests. A lookup can return `10.10.10.30` because the DNS zone contains an A record, even if no machine is configured with that address. Connectivity testing would require a separate network test, and application availability would require testing the relevant service. The lab explicitly warns that its sample addresses are not pingable because no devices have those addresses assigned. **Key takeaway:** A DNS answer confirms record data, not that the destination is operational.\n\n**Glossary:** **DNS resolution**: Obtaining DNS data for a queried name. **Reachability**: Whether a device can be contacted over the network. **A record**: A name-to-IPv4 mapping.
Related Questions
- On Rocky Linux, the DHCP server package is installed with `dnf install _____`.(basic)
- Arrange the steps for deploying and starting a DHCP service on Rocky Linux in the correct administrative order.(intermediate)
- On RHEL-based distributions such as Rocky Linux, the systemd service unit name used to manage the IPv4 DHCP server daemon is `dhcpd`.(basic)
- Select ALL statements that correctly compare Windows DHCP and Linux ISC DHCP as described in the course material.(intermediate)
- Explain how an administrator would investigate a Linux DHCP service problem differently from a Windows DHCP service problem, using only the platform differences covered in the course.(advanced)
Want to practice more questions like this?
Join myBenkio free and practice past questions for your Nigerian university courses with AI explanations for every answer.
Start Practicing Free