Which file on a client can be edited to override DNS results by mapping hostnames to IPs?

Which file on a client can be edited to override DNS results by mapping hostnames to IPs?

• A. Hosts file
• B. DNS cache
• C. Firewall rules
• D. DHCP leases

Answer: (A)

Editing the hosts file on a client lets you override DNS results by providing local mappings of hostnames to IP addresses. The resolver checks this file before asking remote DNS servers, so adding an entry like example.com 203.0.113.5 makes that hostname resolve to the specified IP regardless of what the DNS system would return. This is a local, static override that takes precedence over DNS responses until you change or remove the entry. The DNS cache isn’t something you edit to add new mappings—it’s a stored result that can be cleared, but it doesn’t serve as a persistent mapping. Firewall rules control traffic flow, not hostname-to-IP mappings. DHCP leases determine which IPs a client gets from a network, not how hostnames map to IPs. So the hosts file is the correct place to override DNS on the client.

Editing the hosts file on a client lets you override DNS results by providing local mappings of hostnames to IP addresses. The resolver checks this file before asking remote DNS servers, so adding an entry like example.com 203.0.113.5 makes that hostname resolve to the specified IP regardless of what the DNS system would return. This is a local, static override that takes precedence over DNS responses until you change or remove the entry. The DNS cache isn’t something you edit to add new mappings—it’s a stored result that can be cleared, but it doesn’t serve as a persistent mapping. Firewall rules control traffic flow, not hostname-to-IP mappings. DHCP leases determine which IPs a client gets from a network, not how hostnames map to IPs. So the hosts file is the correct place to override DNS on the client.