I just had the same problem. In my case the mount command reported the / filesystem mounted on /dev/root, but /dev/root didn't exist. Creating a symbolic link (ln -s /dev/sdaX /dev/root) fixed the problem.
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I am having the same error as this post:
https://sourceforge.net/p/raider/discussion/help/thread/04597bca/
/dev/sda is definitely my system disk.
I just had the same problem. In my case the mount command reported the / filesystem mounted on /dev/root, but /dev/root didn't exist. Creating a symbolic link (ln -s /dev/sdaX /dev/root) fixed the problem.