I have a remote Pi with some SD card corruption. Not enough to stop it booting and running, but enough to stop it writing files properly. The problem showed up when I changed some files then rebooted. The changes disappeared ... and a bit of digging revealed that the most likely cause is corruption in the file system.
I talk to it via SSH.
When I ran fsck to check but not fix things, it told me there are problems with the internode count. Whatever that is.
Can I run fsck and tell it to fix this? Maybe make it do the full fsck as part of the boot sequence ... ? Whatever.
I have been reluctant to try this as I don't want to totally kill the system right now.