My modem has reached this level of completion after about 30 days in the / overlay section, about 89%
Why is this section being filled? And how to stop it? Because it creates problems after filling
Filesystem Size Used Available Use% Mounted on
/dev/root 11.3M 11.3M 0 100% /rom
tmpfs 61.1M 640.0K 60.5M 1% /tmp
/dev/mtdblock6 2.9M 2.6M 320.0K 89% /overlay
overlayfs:/overlay 2.9M 2.6M 320.0K 89% /
tmpfs 512.0K 0 512.0K 0% /dev
/dev/mtdblock7 320.0K 196.0K 124.0K 61% /noremove
If you installed any packages or you are adding files in the permanent storage, that will decrease the anyway small overlay amount of space.
What should I do to solve this problem?
All files you create or delete after the installation (except temporary files that go to RAM) take some space from "/overlay". What modifications have you performed after the installation?
After installation, a series of bash files are executed automatically and simple settings such as changing lan, etc. are performed.
A number of packages are also installed, such as snmpd and ..
If the space used increases offer the installation and configuration, perhaps some of the extra packages are writing to the internal flash memory.
Check the contents of /overlay/upper directory.
You should be able to identify, which files consume space.