Filesystems - OpenWrt Wiki
https://openwrt.org/zh/docs/techref/filesystems11.06.2018 · To overcome this limitation OpenWrt uses the remaining portion of the NAND rootfs partition to store an additional read/write jffs2 filesystem which is “overlayed” on top of the rootfs (that is, allowing to read unchanged files from the SquashFS but storing all the modifications made to the jffs2 part).
[OpenWrt Wiki] Extroot configuration
openwrt.org › docs › guide-userNov 28, 2021 · Extroot configuration This article relies on the following: * Accessing OpenWrt CLI * Managing configurations * Managing packages * Managing services Introduction This guide describes how to configure OpenWrt to use a storage device (USB or SATA or SD card or whatever) to expand your root filesystem, to install freely all the packages you need.
[OpenWrt Wiki] Using storage devices
openwrt.org › docs › guide-userOct 25, 2021 · Install file system drivers and create a file system in the partition To use a partition for data storage, it needs to be formatted with a file system. The following is the most simplest (and recommended) default configuration for OpenWrt file system usage.