Settings/Files not being persisted on a AVM FritzRepeater 1750E?

Installing and Using OpenWrt
1

Dear all,

I bought a second AVM FritzRepeater to debug the upgrade issues on my existing one, which would not go from 24.10.x to 25.12.x.

The new one behaves strange: Any files I create (being logged in via SSH) or settings I made in the UI, e.g. setting the hostname, are not being persisted. Looks like the device returns to factory settings every time it reboots.

Did someone experience something similar before? And maybe also find a solution?

I will factory-reset and flash another official image and see, if the behaviour changes.

Kind Regards,

Johannes

2

This behavior is typically observed when the device doesn't have enough space remaining in the flash storage to save files.

Did you customize the image or install additional packages?

What is the output of:

ubus call system board
df -h
mount
3

Thanks for the quick reply. I am currently testing with an official image.

Funny thing is the image was working well with 24.10.6 with the set of packages I installed, but maybe something increased in the 25.12.x release and now there is no more space to safe files.

I’ll compare and report back…

4

OK, using my image there does not seem to be a working overlay mount, even though there seems to be enough space?

Working (official image)

root@OpenWrt:~# df -h
Filesystem                Size      Used Available Use% Mounted on
/dev/root                 4.5M      4.5M         0 100% /rom
tmpfs                    27.3M    208.0K     27.1M   1% /tmp
tmpfs                    27.3M     64.0K     27.2M   0% /tmp/root
tmpfs                   512.0K         0    512.0K   0% /dev
/dev/mtdblock4            7.9M    364.0K      7.5M   5% /overlay
overlayfs:/overlay        7.9M    364.0K      7.5M   5% /
root@OpenWrt:~#

Broken:

root@OpenWrt:~# df -h
Filesystem                Size      Used Available Use% Mounted on
/dev/root                12.3M     12.3M         0 100% /rom
tmpfs                    27.3M    172.0K     27.1M   1% /tmp
tmpfs                    27.3M     80.0K     27.2M   0% /tmp/root
overlayfs:/tmp/root      27.3M     80.0K     27.2M   0% /
tmpfs                   512.0K         0    512.0K   0% /dev
root@OpenWrt:~#

In the mount output I can see that those two lines are missing in “my” image:

/dev/mtdblock4 on /overlay type jffs2 (rw,noatime)                                                                          
overlayfs:/overlay on / type overlay (rw,noatime,lowerdir=/,upperdir=/overlay/upper,workdir=/overlay/work,uuid=on)

I’ll try to reduce the image size and see if this solves the issue.

5

OK, throwing out some packages and I get a “working” image. I.e. the overlay mount is like on the official one.

Thanks for the tip in the right direction @psherman