FortiGate Next Generation Firewall utilizes purpose-built security processors and threat intelligence security services from FortiGuard labs to deliver top-rated protection and high performance, including encrypted traffic.



This article describes the meaning of the 'File System Check Recommended' message and how to handle it.

From the GUI.
From the CLI.
FG6H1E-3 login: admin
Welcome !

WARNING: File System Check Recommended! Unsafe reboot may have caused inconsistency in disk drive.
It is strongly recommended that you check file system consistency before proceeding.
Please run 'execute disk scan 1'
Note: The device will reboot and scan during startup. This may take up to an hour.


The file system check dialogue offers the options to restart the unit and perform a file system check or, if desired, to be reminded later for performing the action in a maintenance window.
File System check is a feature that is checking if the unit was not shutdown properly.

It will do a disk scan when the system boots up to avoid any potential file system errors. 
In fact, if the unit was shutdown without using the proper command (# execute shutdown), during the booting sequence, the FortiGate will check internal files for this log event and, if it cannot find it, the message will be shown.

This behavior is by design  and to secure the disk and file system integrity.
In case of a power loss, data might not be fully committed to a disk write but has been written in parts.

The state of data is then not consistent and this could cause issues.

It is not possible to disable the message but it is possible to automatically run the file system check with the option from GUI, System (Global VDOM) -> Settings -> Auto file system check. Set it to enable.

As the description says:
In the event of a power interruption, automatically check the file system for any errors during boot up.
This will increase the boot time, but is recommended to avoid leaving errors undetected.

The message should no longer be seen once the following two actions have been completed:
- Check of the file system
- Reboot of the unit.

Example of the process from console:
Following an electricity outage, users will receive the message 'File System Check Recommended!'.

FG6H1E-3 login: admin

WARNING: File System Check Recommended! An unsafe reboot may have caused an inconsistency in the disk drive.
It is strongly recommended that you check the file system consistency before proceeding.
Please run 'execute disk scan 1'
Note: The device will reboot and scan the disk during startup. This may take up to an hour.
FG6H1E-3 # execute disk scan 1
scan requested for:  device=/dev/sda1 1/SSD1 status=enable media-status=enable
This action requires the unit to reboot.
Do you want to continue? (y/n)y
Performing scan on the requested disk(s) and rebooting, please wait...
FG6H1E-3 # Scanning the disk...
- unmounting /data2 :  ok
- unmounting /var/log :  ok
- unmounting /var/storage/SSD2-WANOPTXX805C06B2 :  ok
Scanning /dev/sda1. Please wait ...
Scanning /dev/sda1... (100%)
Finished scanning 1 device in 18.21 seconds.
The system is going down NOW !!
Please stand by while rebooting the system.
Restarting system.
FortiGate-601E (21:11-08.13.2019)
Serial number:FG6H1ETB20XXXXXX
RAM activation
CPU(00:000906ea bfebfbff): MP initialization
CPU(01:000906ea bfebfbff): MP initialization
CPU(02:000906ea bfebfbff): MP initialization
CPU(03:000906ea bfebfbff): MP initialization
CPU(04:000906ea bfebfbff): MP initialization
CPU(05:000906ea bfebfbff): MP initialization
CPU(06:000906ea bfebfbff): MP initialization
CPU(07:000906ea bfebfbff): MP initialization
CPU(08:000906ea bfebfbff): MP initialization
CPU(09:000906ea bfebfbff): MP initialization
CPU(0a:000906ea bfebfbff): MP initialization
CPU(0b:000906ea bfebfbff): MP initialization
Total RAM: 16368MB
Enabling cache...Done.
Scanning PCI bus...Done.
Allocating PCI resources...Done.
Enabling PCI resources...Done.
Zeroing IRQ settings...Done.
Verifying PIRQ tables...Done.
Boot up, boot device capacity: 15272MB.
Press any key to display configuration menu...
Reading boot image 3014579 bytes.
Initializing firewall...
System is starting...
FG6H1E-3 login: admin
FG6H1E-3 #

The message does not appear once the check is done and the unit rebooted.
If it is operated an HA cluster, operate on the slave unit, then force a failover and operate again on the slave unit.


The number referenced by 'execute disk scan' is specific to the platform, example below for FGT101F for which it is 259:


FortiGate-101F (global) # execute disk list
Disk Internal        ref: 258 447.1GiB    type: SSD [ATA Micron_5200_MTFD] dev: /dev/sda
  partition ref: 259 440.1GiB, 439.0GiB free  mounted: Y  label: LOGUSEDX0661E0CF dev: /dev/sda1 start: 2048 .