: Devices like routers and smart home hubs often run entirely from a boot ramdisk to ensure high speed and protect the underlying flash storage from excessive wear.
The kernel itself can only directly mount a root file system if it has built-in drivers for the underlying storage hardware and file system. However, monolithic kernels with every possible driver are bloated and inflexible. Instead, modern kernels use . boot ramdisk
A standard initramfs contains:
RAM disks are created by partitioning capacity from system memory (aka RAM) using software, and they provide incredibly fast I/O ( Kingston Technology how-to-root-xiaomi-phone.md - GitHub : Devices like routers and smart home hubs
Once the real root file system is accessible, the system switches to it, and the initramfs is unmounted. the system switches to it