gemetric for Drive doesn't generate disk_total.rrd

[rr-paras-patel]

my some of the servers doen't generate disk_total.rrd.
although it generates
disk_free.rrd
disk_reads.rrd
disk_writes.rrd successfully without any exception or error messages.
Can you give me hint or checklist to cross check this problem.

[hawson]

None of the current scripts appears to generate those metrics. Which script is causing trouble?