HOWTO: Read only rootfs, writes to USB on Linux
What you will need:
- Kernel sources for the system you are booting on
- AUFS patches for the kernel
- A USB drive, preferrably one with reasonably fast write speeds
The goal of this excercise is to create a Linux system that has a read-only root filesystem, with all write activites performed on a USB drive. In this instance, we will boot a Raspberry Pi, with the SDcard used as the read only rootfs, and a USB drive used for all file writes (system logs etc.). This is done to improve reliability, as during our access system project, we found that the SDcard can be a bit fragile if the system is reset often.
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