Troubleshooting Tip: Cannot add second IPsec tunnel in a Aggregate interface

The error 'The Web page cannot be found' may be displayed on the FortiGate GUI when the administrator attempts to add a second interface to the IPsec aggregate. 

Generally, the error occurs because the name has any spaces; the FortiGate shows this space as % instead of displaying the correct name.

Using HTTPS, the following error can be seen:

/api/v2/cmdb/system/ipsec-aggregate/FTNT%2025%FTNT

For the name 'FTNT 2025 FTNT'.

The correct display should be:

/api/v2/cmdb/system/ipsec-aggregate/FTNT\2025\FTNT

Note: As best practice, the space should be avoided when naming any object; use a special character, such as '-_' instead.

FortiGate’s configuration API does not properly handle spaces in object names, causing URL encoding issues that result in GUI errors when managing IPsec aggregate interfaces.

Solution: Rename the tunnel object following the best practices, and do not use spaces in the objects.

Workaround: Use the CLI to add the IPsec tunnels to an aggregate:

config system ipsec-aggregate

    edit "FTNT 2025 FTNT"

        set member "site to site" "site to site 2"

        set algorithm weighted-round-robin

    next

end