FIREWALL SUPPORT CENTER · TECHNICAL KNOWLEDGE BASE
Find where traffic breaks.
Troubleshoot firewall, security, and networking issues with practical guides for enterprise environments.
Explore by Topic
Start with the part of the packet path you need to investigate.
Firewall
Diagnose VPN failures, trace NAT and policy matches, and read packet captures.
Start Here: IPsec VPN Troubleshooting
Tunnel up but no traffic passes? Choose your firewall to follow the checks for your platform.
FortiGate
FortiOS · Check Phase 2 selectors, policy matches, NAT, and the return path.
Palo Alto
PAN-OS · Trace Proxy IDs, Security and NAT rules, and tunnel counters.
Check Point
Gaia R82 · Verify VPN domains or VTIs, SmartConsole logs, and packet flow.
Latest Guides
Read the most recent articles from the knowledge base.
- Cisco Catalyst STP Troubleshooting: IOS XE Commands for Rapid PVST+ and MST
- Aruba AOS-CX STP Troubleshooting: Commands for MSTP and RPVST+
- Check Point Policy Installed but the Rule Still Does Not Match
- Check Point Destination NAT Not Working: Trace an Inbound HTTPS Connection
- Palo Alto Destination NAT Not Working: How to Verify NAT and Security Policy
- Palo Alto Firewall Is Allowing Traffic, but the Application Still Fails
How to Use These Guides
Start with the symptom, confirm the product and software version, and record the traffic flow you expect. Check the result against the same flow after each change.