I have a doubt about boot process, is possible set boot partition from boot if /dev/root fails? like a grub select. I prefer no use berryboot and my install is noobs based. My idea is set a boot partition failover for data corruption on SD card. Any ideas?
No. You could (I believe this is what something like berryboot probably does; I haven't used it) load a minimal root fs, possibly from an initramfs, present the user with options, and then switch the root filesystem (which is what initramfs kernels always do), but obviously there is a bit of work involved.
Alternately, you could write your own bootloader code, but this is even more work, and may require some proprietary knowledge (I'm not sure).
You need to edit
/boot/cmdline.txt and define
root=PARTUUID=, for example
You can have multiple partitions, up to 3 (except boot one), with different OS.
To find your destinated PARTUUID you can use this command:
ls -l /dev/disk/by-partuuid/
Each of rootfs partitions have to have own
/etc/fstab with its PARTUUID
You can prepare two folders
/boot/os2 with separated
cmdline.txt. Than just move content of needed os to /boot and it works just like full separated dual boot.