300-430 Question 160
Select 2A network administrator is deploying a captive portal on a Cisco wireless network to provide guest Wi-Fi access. The captive portal requires users to accept terms and conditions before gaining network access. After deployment, some users report that they are unable to see the captive portal when they connect to the Wi-Fi network. Which of the following could be the cause of this issue?
- A
The DNS redirect for the captive portal is not configured correctly.
- B
The wireless LAN is using an incorrect VLAN for guest traffic.
- C
The client devices are using static IP addresses instead of DHCP.
- D
The captive portal certificate is expired.
- E
802.1X authentication is incorrectly configured on the guest SSID.
Show answer and explanation
Correct answers: A, C
Explanation
For a captive portal to function correctly, DNS redirection must be properly configured to direct users to the portal page when they first connect to the network. Additionally, guest devices should typically use DHCP to ensure they receive correct IP settings, including the default gateway and DNS server, which are essential for accessing and being redirected to the captive portal.
- A. Correct.
If the DNS redirect for the captive portal is not configured correctly, client devices may not be redirected to the portal after connecting to the network, causing the users to miss the captive portal page.
- B. Incorrect.
While an incorrect VLAN assignment could lead to connectivity issues, it does not specifically prevent the captive portal from displaying.
- C. Correct.
If client devices are using static IP addresses instead of obtaining one via DHCP, they might bypass the captive portal or fail to connect to the correct subnet where the portal is hosted.
- D. Incorrect.
An expired captive portal certificate would cause certificate warnings, but it would not prevent the captive portal itself from appearing.
- E. Incorrect.
802.1X authentication is not typically used for guest networks with captive portals. Misconfigurations here might cause other issues but would not directly affect captive portal visibility.