Solved: How do I fix Non-FIPS FortiSwitches offline when managed by FortiGate configured in FIPS-CC mode

This article describes how a FortiSwitch that does not support FIPS can be managed by a FortiGate in FIPS mode.

Scope

FortiGate in FIPS mode and FortiSwitch in non-FIPS mode.

Solution

FortiGate in FIPS-CC mode impose restrictions in different settings, especially related to supported algorithms for secure communication channels.

Not all FortiSwitch models support FIPS mode, and even the models that do support, may not be operating with FIPS mode enabled.
When FIPS mode is enabled in a FortiGate, the below setting is enabled by default.

# config switch-controller global
set fips-enforce enable
end

If the FortiSwitch does not support FIPS or it is not configured for FIPS, it will show offline in FortiGate after authorizing it.

To resolve the issue, the following setting needs to be disabled so the negotiation of CAPWAP tunnel happens without any issue.

# config switch-controller global
set fips-enforce disable
end