Can't boot R5C if TF Card is inserted

[knightfox]

Hi all,

I have successfully upgraded my R5C using TF Card (65GB extreme pro sandisk) with FriendlyWrt with Docker, based on OpenWrt 24.10. Flashed using win32diskimager.

After that I formated my 64GB extreme pro sandisk to ext4. But my R5C is unable to boot to openwrt if the card is inserted. The red LED on R5C is not blinking at start and nothing happens.

My R5C boot normally after I took out the card and power up my R5C. In LUCI > System > Mount Points, my card will shows up if I inserted the card while my R5C is running. But after reboot, it will fail to boot up and the red LED is not blinking again.

Please help!

[Yucar]

Possible Causes

- Bootloader conflict: When a TF card is inserted, the device may attempt to boot from the card instead of internal storage, leading to a freeze.
- Ext4 format: Some firmware or bootloaders do not handle ext4-formatted TF cards well during boot.
- Partition table: If the card has a non-standard MBR/GPT, the system may be confused during boot.
- Driver or kernel module: FriendlyWrt/OpenWrt sometimes requires specific mount configuration to recognize the card properly.

Troubleshooting

- Try reformatting the card: Use FAT32 or ext3 instead of ext4 to check.
- Check boot priority: Enter U-Boot or BIOS (if available) to ensure the device boots from eMMC/NAND first, not from the TF card.
- Unmount before reboot: If the card is mounted in LUCI, unmount it and reboot to see if it improves.
- Create a clean partition: Use fdisk or gparted to delete the entire partition, create a single new partition, and then format it.
- Check the kernel log: When mounting the TF card during runtime, use dmesg to view error messages related to drivers or the filesystem.

If the purpose is to save data, you can mount the TF card after the system has finished booting. If you want the card to work from the start, ensure the bootloader is not redirected to the TF card.