I found I needed more disc space for the rrd files. I added a disc and copied the files to the new disk and created a symbolic link form the old directory point to the new. At that point all of the graphs failed with ERROR: String ends after the = sign on ‘CDEF:inB=’ as the error. I change back to the old directory the graphs display. When pointing to the new directory the files appear to update with the scan.
$config['rrd_dir'] = '/new/path';