On SLES 12.2 I do the following as root user:
mkdir -p /some/directory/ramdisk
chown -R simpleuser:users /some
chmod 777 /some/directory
chmod 777 /some/directory/ramdisk
Then I add this to /etc/fstab
ramfs /some/directory/ramdisk ramfs defaults 0 0
What I expect is a ramfs mounted to /some/director/ramdisk, owned by simpleuser and users, with permissions set to 777.
Surprisingly, after rebooting the machine, the owner of /some/director/ramdisk is root:root, and the permissions have changed to something more restrictive. I deem that more of a feature than a bug, but that behaviour is really annoying in the environment I use it in.
Currently I do an explicit change of ownership and permissions prior to starting the application that uses the ramdisk (in the respective script, with sudo), but I deem that not very elegant.
Any hint what causes the changes, and how to prevent them ?