Forti OS 7.4.12 – Is it possible to completely disable local Alert/Error/Critical logs?

Can you share an example of a log that you are referring to?

Hi ​@ahmadking22 

The log severity filter in FortiOS works on an inclusive threshold basis. The default severity is information, which means all logs at the information level and above (including notification, warning, error, critical, alert, and emergency) are logged.
The severity levels are:
emergency
alert
critical
error
warning
notification
information
debug

Setting the severity to a higher number (e.g., error) would only log error, critical, alert, and emergency — it would not exclude Alert/Error/Critical logs.

While you cannot disable Alert/Error/Critical logs entirely, you can use free-style log filtering  to exclude specific log messages based on criteria such as logid.

config log memory filter  
config free-style  
edit 1  
set category event  
set filter "logid 0100041001"  
set filter-type exclude  
next  
end  
end  

This allows you to exclude specific log messages by their unique logid, but you would need to identify and add each individual log ID you want to suppress

​@ahmadking22 
You can disable memory logging while navigating in the GUI to Log & Report → Log Settings → Local Logs and disable Memory logging.
This is because at 40F, a hard disk might not be present:

FGT40F # get hardware status
Model name: FortiGate-40F
Hard disk: not available    -------  no hdd to save logs but only memory (RAM)
USB Flash: not available

If this is the answer, please mark it as a solution to help others find it easily.