On my Debian server I am running Apache. Today I found that I am unable to create files in all of the website directories. So for example I have /var/www/testsite. I change to that directory.
Then the following command
cp index.php test results in
cp: cannot create regular file test': Invalid argument'.
Both the normal and root users are unable to create a file. Other commands souch as 'echo hello > test' fail as well.
mkdir test succeeds. So I can create directories, but not files.
The directory permissions are 755, same as all the other directories. I can create files in the other directories on the system.
lsattr . but am not sure what I was looking at. The result was