树莓派Openwrt扩容Overlay（仅限squashfs固件）

1.查看当前磁盘信息

df-h

root@BleachWrt:~# df -h
Filesystem                Size      Used Available Use% Mounted on
/dev/root               310.3M    310.3M         0 100% /rom
tmpfs                     1.9G     22.2M      1.8G   1% /tmp
/dev/loop0              711.9M     81.0M    630.9M  11% /overlay
overlayfs:/overlay      711.9M     81.0M    630.9M  11% /
/dev/mmcblk0p1           63.9M     19.6M     44.2M  31% /boot
tmpfs                   512.0K         0    512.0K   0% /dev
cgroup                    1.9G         0      1.9G   0% /sys/fs/cgroup
overlayfs:/overlay      711.9M     81.0M    630.9M  11% /opt/docker

2.利用空余存储新建分区

fdisk /dev/mmcblk0：修改为对应的硬盘名称

root@BleachWrt:~# fdisk /dev/mmcblk0

Welcome to fdisk (util-linux 2.38.1).
Changes will remain in memory only, until you decide to write them.
Be careful before using the write command.

This disk is currently in use - repartitioning is probably a bad idea.
It's recommended to umount all file systems, and swapoff all swap
partitions on this disk.


Command (m for help): p                           <=====查看当前分区信息

Disk /dev/mmcblk0: 119.08 GiB, 127865454592 bytes, 249737216 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: dos
Disk identifier: 0x5452574f

Device         Boot  Start     End Sectors Size Id Type
/dev/mmcblk0p1 *      8192  139263  131072  64M  c W95 FAT32 (LBA)
/dev/mmcblk0p2      147456 2244607 2097152   1G 83 Linux
                              ^
                        (分区2的end位数值)

Command (m for help): n                            <=====新建分区
Partition type
   p   primary (2 primary, 0 extended, 2 free)
   e   extended (container for logical partitions)
Select (default p): p                              <=====设置新建分区为主分区
Partition number (3,4, default 3): 3               <=====设置新建分区号为3
First sector (2048-249737215, default 2048): 2244608    <=====此数值需大于分区2的end位数值
Last sector, +/-sectors or +/-size{K,M,G,T,P}(2244608-249737215, default 249737215):<=回车

Created a new partition 3 of type 'Linux' and of size 118 GiB.

Command (m for help): p                            <=====查看当前分区信息
Disk /dev/mmcblk0: 119.08 GiB, 127865454592 bytes, 249737216 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: dos
Disk identifier: 0x5452574f

Device         Boot   Start       End   Sectors  Size Id Type
/dev/mmcblk0p1 *       8192    139263    131072   64M  c W95 FAT32 (LBA)
/dev/mmcblk0p2       147456   2244607   2097152    1G 83 Linux
/dev/mmcblk0p3      2244608 249737215 247492608  118G 83 Linux

Command (m for help): w                             <=====保存分区信息
The partition table has been altered.
Syncing disks.

3.格式化新建的分区

mkfs.ext4 /dev/mmcblk0p3：执行完出现done即格式化成功

root@BleachWrt:~# mkfs.ext4 /dev/mmcblk0p3
mke2fs 1.47.0 (5-Feb-2023)
Found a dos partition table in /dev/mmcblk0p3
Proceed anyway? (y,N) y
Discarding device blocks: done
Creating filesystem with 30936576 4k blocks and 7741440 inodes
Filesystem UUID: 49694d4a-62db-4365-82dd-1005604e63d5
Superblock backups stored on blocks:
        32768, 98304, 163840, 229376, 294912, 819200, 884736, 1605632, 2654208,
        4096000, 7962624, 11239424, 20480000, 23887872

Allocating group tables: done
Writing inode tables: done
Creating journal (131072 blocks): done
Writing superblocks and filesystem accounting information: done

4.挂载新分区，并将overlay分区的配置文件导入新分区

mkdir -p /mnt/mmcblk0p3：创建用于挂载的目录

mount /dev/mmcblk0p3 /mnt/mmcblk0p3/：挂载新分区至挂载目录

ls /overlay/：查看/overlay/分区下的内容

root@BleachWrt:~# ls /overlay/
upper       work

cp /overlay/* /mnt/mmcblk0p3/：将/overlay/分区下的内容复制到挂载目录

root@BleachWrt:~# ls /mnt/mmcblk0p3/
lost+found  upper       work

5.打开web端，创建挂载点

在“UUID”中选择新建的分区，挂载点选择“作为外部overlay（/overlay）使用”，勾选“启用此挂载点”

6.回到终端执行reboot命令

reboot：重启电脑使配置生效

7.在web端打开“软件包”，查看空间是否增加