What is the primary DNS server IP configured on pfSense in this lab?

What is the primary DNS server IP configured on pfSense in this lab?

• A. 163.128.78.93
• B. 163.128.80.93
• C. 65.86.24.136
• D. 65.86.1.1

Answer: (A)

The main idea here is how pfSense handles DNS requests. When you configure DNS servers in pfSense, the first address you list is treated as the primary DNS server. pfSense will send all DNS queries to that primary server first, and only if it can’t reach or get a response from it will it try the next one in the list as a backup. In this lab setup, the pfSense box is configured with 163.128.78.93 as the primary DNS server. That means all client name lookups are sent to that IP first, making it the default resolver for the network. If that server were unavailable, pfSense would fall back to the secondary DNS server(s) you’ve configured. You can verify this by checking the DNS settings in pfSense (System > General Setup) to see which IPs are listed and in what order, or by performing a DNS lookup and noting which server responds. The other IPs listed (such as 163.128.80.93 or 65.86.x.x) would serve as backups or alternatives, not the first contact, which is why they aren’t the primary in this lab.

The main idea here is how pfSense handles DNS requests. When you configure DNS servers in pfSense, the first address you list is treated as the primary DNS server. pfSense will send all DNS queries to that primary server first, and only if it can’t reach or get a response from it will it try the next one in the list as a backup.

In this lab setup, the pfSense box is configured with 163.128.78.93 as the primary DNS server. That means all client name lookups are sent to that IP first, making it the default resolver for the network. If that server were unavailable, pfSense would fall back to the secondary DNS server(s) you’ve configured.

You can verify this by checking the DNS settings in pfSense (System > General Setup) to see which IPs are listed and in what order, or by performing a DNS lookup and noting which server responds. The other IPs listed (such as 163.128.80.93 or 65.86.x.x) would serve as backups or alternatives, not the first contact, which is why they aren’t the primary in this lab.