1. Preparation
1.Connect a monitor and a USB keyboard to the HDMI and USB ports of your TNAS.
2.Power on the device. During POST (Power-On Self-Test), repeatedly press the Esc key to enter the BIOS setup.
BIOS Keyboard Shortcuts
Key Function
← / → Switch between the top menu tabs (Main, Boot, etc.)
↑ / ↓ Move between options on the current page
Enter Open a submenu or confirm a selection
Esc Return to the previous menu
F4 Save changes and exit BIOS
2. Configuration
Please follow the instructions for your TNAS model.
Models Supported
F2-425 Plus, F4-425 Plus, F4-425 Pro, F2-424, F4-425, F-424 Pro, F6-424, F6-425 Pro, F4 SSD, F8 SSD, F8 SSD Plus
These models have TOS Boot First enabled by default. When enabled, the system always boots from the storage device containing TOS.
To boot from another device (such as a USB drive, M.2 SSD, or a specific hard drive), you must first disable this feature.
Step 1：Enter the BIOS and use the ← / → keys to open the Boot tab.
Step 2：Select TOS Boot First, press Enter, choose Disabled, then press Enter again to confirm.
Step 3：Select Boot Option #1, press Enter, choose the desired boot device with the ↑ / ↓ keys, and press Enter to confirm.
Step 4：After verifying all settings, press F4 to save and exit BIOS. The NAS will restart automatically and boot from the selected device.
Models Supported
F2-425, F4-425
Depending on the number of installed hard drives and USB storage devices, follow one of the scenarios below.
Scenario 1: One Hard Drive + One USB Drive
No additional priority configuration is required. Simply change Boot Option #1.
Step 1：Enter the BIOS and switch to the Boot tab.
Step 2：Select Boot Option #1, press Enter, choose the desired boot device, and confirm.
Step 3：Press Esc to return to the Boot menu and verify that Boot Option #1 displays the selected device.
Scenario 2: Multiple Hard Drives or Multiple USB Storage Devices
When multiple bootable devices are present, changing only Boot Option #1 is not sufficient. You must first configure the boot priority within the corresponding device group.
A. Set a Specific Hard Drive as the Primary Boot Device
Step 1：On the Boot page, select UEFI Hard Disk Drive BBS Priorities, then press Enter.
Step 2：Select Boot Option #1, press Enter, and choose the hard drive you want to boot from.
Step 3：Press Esc to return to the Boot page and verify that Boot Option #1 now shows the selected hard drive.
Step 4：Press F4 to save the settings and exit BIOS. The NAS will restart automatically and boot from the selected hard drive.
B. Set a Specific USB Drive as the Primary Boot Device
Step 1：On the Boot page, select UEFI USB Drive BBS Priorities, then press Enter.
Step 2：Select Boot Option #1, press Enter, choose the desired USB drive, and confirm.
Step 3：Press Esc to return to the Boot page. Select Boot Option #1, press Enter, and choose the USB drive that was configured as the highest-priority USB boot device.
Step 4：Press F4 to save the settings and exit BIOS. The NAS will restart automatically and boot from the selected USB drive.
Need Assistance?
If you encounter any issues during the operation, you can leave a comment below this post or contact our official after-sales support directly for technical assistance. https://salesiq.zohopublic.com/signatur ... 97d0be8892, We are committed to providing you with the best possible service.