Description |
This article describes the criteria that the Disk Usage Calculation Widget uses to calculate percentage usage. |
Scope | FortiOS. |
Solution |
Let’s consider that the FortiGate for this example has two 240 GB SSDs for storage, and the Widget shows that it is using a total of 52%:
If using the command 'diag hardware deviceinfo disk' the following results will appear:
Fortilab # diag hardware deviceinfo disk
Disk SSD1 ref: 255 223.6GiB type: SSD [ATA INTEL SSDSC2KB24] dev: /dev/sda partition ref: 1 220.1GiB, 75.2GiB free mounted: Y label: NEBUCHADNEZZAR dev: /dev/sda1 start: 2048
Disk SSD2 ref: 16 223.6GiB type: SSD [ATA INTEL SSDSC2KB24] dev: /dev/sdb partition ref: 17 62.7GiB, 62.4GiB free mounted: Y label: RA88ITH0L3 dev: /dev/sdb1 start: 2048 partition ref: 18 63.7GiB, 63.7GiB free mounted: N label: dev: /dev/sdb2 start: 133625856 partition ref: 19 85.0GiB, 85.0GiB free mounted: N label: dev: /dev/sdb3 start: 267249664
Disk SYSTEM(boot) 14.9GiB type: SSD [ATA 16GB SATA Flash] dev: /dev/sdc partition 247.0MiB, 148.0MiB free mounted: N label: dev: /dev/sdc1(boot) start: 1 partition 247.0MiB, 147.0MiB free mounted: Y label: dev: /dev/sdc2(boot) start: 524289 partition ref: 35 14.2GiB, 13.7GiB free mounted: Y label: dev: /dev/sdc3 start: 1048577
Total available disks: 3 Max SSD disks: 2 Available storage disks: 2
Even though this unit has 2x240GB for storage, the Widget only gets the usage from the mounted devices. If looking closely at the output from above, it is noticeable that only the partitions sda1 and sdb1 are mounted, check the flag 'mounted: Y' for these partitions.
Looking at sda1 and sdb1 specifically:
partition ref: 1 220.1GiB, 75.2GiB free mounted: Y label: NEBUCHADNEZZAR dev: /dev/sda1 start: 2048 partition ref: 17 62.7GiB, 62.4GiB free mounted: Y label: RA88ITH0L3 dev: /dev/sdb1 start: 2048
Total: 220.1 + 62.7 = 282.8 Free : 75.2 + 62.4 = 137.6 ============================= 145.2 Used (51.34%, around ~52%)
This concludes how the calculation is performed by the Widget, it is not counting the usage for the disk as a whole, it is instead showing the usage of the mounted partitions. |
The Fortinet Security Fabric brings together the concepts of convergence and consolidation to provide comprehensive cybersecurity protection for all users, devices, and applications and across all network edges.
Copyright 2025 Fortinet, Inc. All Rights Reserved.