Technical Tip: Explanation of FortiGate Disc Scan Behavior

[druksha]

Description

This article describes the behavior of a FortiGate when it is rebooted after not having followed the correct shutdown or reboot procedure.

Scope

FortiGate v5.2.3 and newer.

Solution

The FortiGate will boot and perform a file system check of the boot partition to avoid any critical issues:

##### Power-OFF and ON

FortiGate-92D (17:35-08.07.2014)

Ver:05000005

Serial number:FGT
RAM activation
CPU(00:000106ca bfebfbff): MP initialization
CPU(01:000106ca bfebfbff): MP initialization
CPU(02:000106ca bfebfbff): MP initialization
CPU(03:000106ca bfebfbff): MP initialization
Total RAM: 2048MB
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 1422060 bytes.
Initializing firewall...
System is starting...
Starting system maintenance...
Scanning /dev/sda2... (100%)   }---- Boot drive is scanned at the first boot

FGT login: admin
Password: **********
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 17'
Note: The device will reboot and scan during startup. This may take up to an hour.

At this point, the FortiGate is up and running with the boot drive scanned. However, the log drive, whose size is much bigger than the boot drive, will not be scanned automatically to avoid a long downtime period.  This is by design.

Log in to the GUI.

A message indicating that a 'File System Check Recommended' will appear.
Confirm the disc scan so the FortiGate will be rebooted, and press the 'Reboot and check file system' button.

 

The system is going down NOW !!

Please stand by while rebooting the system.
Restarting system.
FortiGate-92D (17:35-08.07.2014)
Ver:05000005
Serial number:FGT
RAM activation
CPU(00:000106ca bfebfbff): MP initialization
CPU(01:000106ca bfebfbff): MP initialization
CPU(02:000106ca bfebfbff): MP initialization
CPU(03:000106ca bfebfbff): MP initialization
Total RAM: 2048MB
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 1422060 bytes.
Initializing firewall...
System is starting...
Scanning /dev/sda3... (100%)      }---- Log drive is being scanned

FortiGate login:

All the file systems have now been scanned, and it is safe to use the FortiGate.

To initiate a File System Check using CLI:

1. Check the partition reference number.
   

   FGT # execute disk list

   Disk SSD ref: 16 447.1GiB type: SSD [ATA INTEL SSDSC2KB48] dev: /dev/sdb
   partition ref: 17 440.1GiB, 439.0GiB free mounted: Y label: LOGUSEDXF21F7069 dev: /dev/sdb1 start: 2048

2. Initiate disk scan using the command 'execute disk scan <partition ref:>'.
   
   FGT # execute disk scan 17 <- this is for partition 17.
   scan requested for: device=/dev/sdb1 17/SSD status=enable media-status=enable
   This action requires the unit to reboot.
   Do you want to continue? (y/n)
   

It is not possible to disable the message, but it is possible to automatically run the file system check. Refer to this document Run a File System Check Automatically.