Connectivity Issues with Fortigate Firmware v7.4.12

Hi cruzer,

The FG-100F has a direct, supported upgrade path from FortiOS 7.2.13 to 7.4.12, so the upgrade path itself does not appear to be the issue.

One thing I would specifically check is whether the affected internal connectivity involves FortiLink/FortiSwitch/VLANs. There is a documented v7.2 → v7.4 upgrade issue where a FortiLink interface with non-default allowaccess settings can be removed, along with dependent VLANs or FortiSwitch configuration.

error log can help confirm this:

diagnose debug config-error-log read

Technical Tip — FortiLink interface removed after v7.2 → v7.4 upgrade

If FortiLink is not involved, I would focus on one internal service that fails on 7.4.12 but works on 7.2.13 and compare its interface, route, policy, and connectivity path.

There is also a documented 100F/101F shared-port speed change during certain upgrades, but Fortinet notes that upgrades from v7.2.9 onward are not affected, so it does not appear applicable to a 7.2.13 → 7.4.12 upgrade.

Hope this helps narrow down the cause.

Also, when you update us with results of your next upgrade attempt, let us know if you have anything in “diag debug config-error-log read” after the upgrade..
One more thing; elaborate a little more about “issues with some of our services”, especially if the problem with external user accesses with VIP, or without VIP but over VPN, or even with internal user access, etc.

Toshi 

Hi Toshi,

There were 2 issues that I know of and they are both services that are internal to our network. There were no VPN issues but it seems to be just on our HQ branch, other branches did not have any issues.  I will use that command you gave me and will update everyone next week.

Thanks much!  

Fellow Forti Geeks!  I am happy to say that I was able to resolve the issue with upgrading from version 7.2.13 to version 7.4.12  

It was this command that I had to enable:  “set allow-traffic-redirect enable”  I’m guessing around FortiOS 7.4.10, Fortinet changed its default from enabled to disabled.  

Thanks all!  Mabuhay!