Open /usr/share/cagefs/cagefsctl.py and find def tmpwatch():
Replace string (line 3922 in cagefs-5.5-6.4.el6.cloudlinux.x86_64):
subprocess.call(cmd, stderr=dev_null, stdout=dev_null)
with this code, saving correct identing for python:
if VERBOSE:
subprocess.call(cmd)
else:
subprocess.call(cmd, stderr=dev_null, stdout=dev_null)
Then run:
cagefsctl -v --tmpwatch
Output of this command should help you to fix the problem.