Technical Tip: Error 'Duplicate Entry Found' When Configuring Backup IPSec VPN Tunnel with Existing Tunnel’s Remote Gateway Address.

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Description	This article provides a workaround and solution for the error 'Duplicate Entry Found' which is encountered while configuring a backup IPSec VPN tunnel using the 'Custom IPSec Tunnel' option to an existing tunnel’s remote gateway address.
Scope	FortiGate v7.6.0.
Solution	When configuring a redundant IPSec tunnel to an existing tunnel’s remote gateway IP using the 'Custom IPSec Tunnel' option, the error 'Duplicate Entry Found' may appear. Primary Tunnel: Secondary Tunnel: This occurs even when using a different WAN interface than the one assigned to the primary tunnel. This issue has been resolved in v7.6.1. Workaround: Use the option 'IPsec tunnel from template' when creating a backup tunnel. OR use the CLI commands. General debug information required by FortiGate TAC for investigation: TAC Report: 'execute tac report'. Configuration file of the FortiGate. Fortinet Support Tool data: Troubleshooting Tip: Collect GUI slowness and errors debugs via Fortinet Support Tool