PCNSE Troubleshoot Practice Question
An engineer is troubleshooting an issue where GlobalProtect users are unable to connect to the portal. The portal is configured with a certificate signed by an internal CA. Users can reach the portal's IP address from the internet, but the connection fails. The firewall log shows 'TLS handshake failed'. What is the most likely cause?
⚠ Common exam trap
Many candidates confuse a certificate name mismatch (subject name vs. URL) with a trust issue, but the 'TLS handshake failed' log entry specifically points to a failure in the certificate chain validation, not a name mismatch, which would produce a different error or warning.
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
The client does not trust the certificate authority that signed the portal certificate
The firewall log shows 'TLS handshake failed', which indicates that the SSL/TLS negotiation between the GlobalProtect client and the portal failed. Since users can reach the portal's IP address from the internet, the issue is not network connectivity but certificate validation. The most common cause is that the client does not trust the internal CA that signed the portal certificate, so the client rejects the certificate during the TLS handshake, causing the failure.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
The portal service is not running
Why it's wrong here
If it were not running, the IP would not be reachable.
- ✗
The portal's IP address is not routable from the internet
Why it's wrong here
Users can reach the IP, so routing works.
- ✗
The portal certificate's subject name does not match the portal URL
Why it's wrong here
If it matched, but the CA is not trusted, the handshake still fails.
- ✓
The client does not trust the certificate authority that signed the portal certificate
Why this is correct
The TLS handshake fails because the client cannot verify the server certificate.
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JA
Written by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
This PCNSE practice question is part of Courseiva's free Palo Alto Networks certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the PCNSE exam.