Hello David,

> A fsck will be performed on system startup, long before anything in
> /etc/rc.local gets run. I know you can force an fsck on boot using
> /boot/cmdline.txt but I don't think you can prevent one.

>> So, RPi or the OS, seems to make changes to the filesystem / MBR or what
>> else, which cannot be recovered by RPi itself, but a "normal" Linux
>> machine can handle this without even alerting about any trouble.

> If this is happening the card needs to be replaced. If it wasn't a Zero
> I'd suggest booting from a USB stick for better reliability, but as an
> SD card is the only option, a high endurance version is probably
> worthwhile.

I have seen a Pi starting form USB stick without a SD card inserted.
You then first need to write the write once only OTP-bit in the machine.
It then checks if there is an USB disk to start from the Pi 3B.
I am not sure if that OTP-bit is usable in the older Pi's and Zero machines.

Henri.

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