Troubleshooting Tip: How to fix the issue when the FortiGate update traffic does not work through another device

[anikolov]

Description	This article describes a possible cause and solution for FortiGate, which is not updating.
Scope	FortiGate, FortiSASE.
Solution	To identify an issue with the update of a FortiGate, the KB article below explains all of the steps to troubleshoot it: Troubleshooting Tip: Failure on update or contact FortiGuard In case the debug from the update daemon returns messages similar to the output below: "Cert error 19, self signed certificate in certificate chain." "Server certificate failed verification. Error: 19 (self signed certificate in certificate chain), depth: 1, subject: <certificate>" "SSL_connect failes: error:1416F086:SSL routines:tls_process_server_certificate:certificate verify failed" "Failed SSL connecting (5,0,Success)" It might be the case that there is another device blocking the FortiGate from reaching FortiGuard. In the sample logs above, it was another FortiSASE which a deep inspection of the traffic was compromising the update. Setting this traffic to a certificate inspection fixes the issue.