Read only root file system to preserve eMMC

Hello everyone,
I’m designing a board on which an iMX6ULL will be installed.
The product does not have a display or buttons but only an ON / OFF switch which cuts off the total power supply.
The customer who will use it can switch it off and on at any time.
I would like to preserve the eMMC and I have read various posts here, but I am not an expert and I would like some help.
I read about using “read-only root file system” but how do I do this?
I use an image built with Yocto and uploaded to the eMMC using Easy Installer, is it enough for it to be read-only?
Doing so will preserve the eMMC by always allowing a secure boot?
Thank you in advance.

Hi @MaxMax

Thanks for writing to the Toradex Support.

I would like to preserve the eMMC and I have read various posts here, but I am not an expert and I would like some help

Colibri iMX6ULL features NAND Flash not eMMC or are you talking about external Flash?

I read about using “read-only root file system” but how do I do this?

You need to built a special image with read-only rootfs.

I use an image built with Yocto and uploaded to the eMMC using Easy Installer, is it enough for it to be read-only?

What settings did you use for this image?

Doing so will preserve the eMMC by always allowing a secure boot?

What do you mean exactly with secure boot?

As already said iMX6ULL feature NAND Flash which uses UBI FileSystem. Until Bsp 2.8, UBI FileSystem was sensible to PowerCuts. With Bsp 3.0.4, we have not see any issue regarding Files being corrupt due to unexpected PowerCuts.

Anyhow this depends also on your application. If lot of data are written during long time, then power-cut can lead to corruption of the data in any media.

Best regards,
Jaski

Sorry I don’t have an external eMMC, intended as NAND Flash.
What settings do you mean?
There will be little written data in my application.
By safe boot I mean it won’t crash during boot.
The final application, which will be used by the customer, will not have keyboards or displays, but only an on-off switch, therefore it is important that the start always occurs, regardless of how it was turned off
I have no idea how to create a read-only rootfs :frowning:
Thanks

Hi @MaxMax

Please have a look here.

Best regards,
Jaski