Which action helps refresh DNS information on a Windows host during troubleshooting?

Which action helps refresh DNS information on a Windows host during troubleshooting?

• A. Disable DHCP
• B. Flush DNS cache
• C. Reinstall network driver
• D. Disable firewall permanently

Answer: (B)

Refreshing DNS information on a Windows host means clearing the DNS resolver cache so the system makes fresh name-to-IP lookups. The DNS cache saves recent query results to speed things up, but if those cached entries are outdated or incorrect, you can run into resolution problems. Flushing the cache forces Windows to discard those entries and perform new lookups, which often fixes issues after a domain changes its IP address or when stale data is causing failures. In practice, you’d run ipconfig /flushdns in an elevated command prompt. After flushing, try accessing the site or pinging the hostname again to verify that the latest DNS data is being used. The other options don’t directly refresh DNS information: disabling DHCP, reinstalling the network driver, or keeping the firewall off can cause unrelated issues and don’t address stale DNS cache.

Refreshing DNS information on a Windows host means clearing the DNS resolver cache so the system makes fresh name-to-IP lookups. The DNS cache saves recent query results to speed things up, but if those cached entries are outdated or incorrect, you can run into resolution problems. Flushing the cache forces Windows to discard those entries and perform new lookups, which often fixes issues after a domain changes its IP address or when stale data is causing failures.

In practice, you’d run ipconfig /flushdns in an elevated command prompt. After flushing, try accessing the site or pinging the hostname again to verify that the latest DNS data is being used. The other options don’t directly refresh DNS information: disabling DHCP, reinstalling the network driver, or keeping the firewall off can cause unrelated issues and don’t address stale DNS cache.