Troubleshooting Tip: Explaining the error 'previous I/O error to superblock detected'

[sahmed_FTNT]

Description	This article describes why, in some cases, it is possible to see the 'previous I/O error to superblock detected' error in the Console output.
Scope	FortiGate.
Solution	The following error may be observed in the console or events: previous I/O error to superblock detected previous I/O error to superblock detected previous I/O error to superblock detected This error means that the system was unable to read/write to some cells on the disk. It might be caused by firmware (wrong/incomplete write cycle terminated by the power cycle or so) or by hardware failure in some parts/tracks/cells of the disk. It is suggested to reboot the device and observe if the errors will persist. Otherwise, it is possible to perform below steps: Take a configuration backup of the device: Configuration backups and reset - FortiGate administration guide. Format the bios in the device and re-write the same firmware again: Technical Tip: Formatting and loading FortiGate firmware image using TFTP. Check crash logs on the FortiGate and confirm if the following logs are seen continously :  diagnose debug crashlog read EXT2-fs (sda2): previous I/O error to superblock detected EXT2-fs (sda2): previous I/O error to superblock detected Run hardware inspection test for the disk and check the results:  diagnose hardware test disk file-data diagnose hardware test disk file-data2 diagnose hardware test disk hdd-block-wrv diagnose hardware test disk file-varlog Technical Tip: RMA - HQIP test (with hardware test image)  Technical Tip: RMA: HQIP test (with built-in FortiOS diagnostic commands)  Format the log disk as well ( Run a command: 'exec formatlogdisk').  Note: Running this command will cause the FortiGate to reboot.  Restore the configuration and observe the unit: Configuration backups and reset - FortiGate administration guide. If an error similar to 'previous I/O error to superblock detected' is still received, move the ticket to the RMA Team, as the device is faulty.