Cpanel showing incorrect disk usage

Issue:
Sometime Cpanel may show Zero Disk usage for all the domains or there might be a  Mismatch between the disk usage in backend and Cpanel frontend.

Solution:

1. Check whether /home partition has been mounted with 'usrquota' option (defaults,usrquota in /etc/fstab)

# cat /etc/fstab| grep home
LABEL=/home  /home    ext3    defaults,usrquota  1 2

# quotacheck -c /home
# quotaon /home

2. Also Check the option WHM >> Server Configuration >> Tweak Settings >> System --- Disable Disk Quota display caching