Technical Tip: Unable to connect SSL VPN on Loopback

Description
This article provides a solution if the SSL VPN connection fails due to policy denial.
No logs on the debug command related to SSL VPN are found during the issue.

diagnose debug reset
diagnose debug app sslvpn -1
diagnose debug en

To Stop the Debugs:

diagnose debug disable

diagnose debug reset

Scope

FortiGate.

Solution

Run a debug command to check the SSL VPN traffic.

diagnose debug reset
diagnose debug flow sh fu en
diagnose debug flow filter addr <IP of sslvpn>
diagnose debug flow trace start 100
diagnose debug en

To stop the debugs:

diagnose debug disable

diagnose debug reset

Getting error on policy deny as below:

id=20085 trace_id=1273 func=fw_local_in_handler line=410 msg="iprope_in_check() check failed on policy 0, drop"

Create a specific policy from the source interface where the connection is initiated to the Loopback interface.
Go to Policy & Object -> IPv4 policy/Firewall policy and 'Create New'.