Undercloud Upgrade failed

Issue

• Ugrading the undercloud fails and the following error message is seen in /home/stack/.instack/install-undercloud.log

2018-01-30 12:32:26 - Notice: Finished catalog run in 402.49 seconds
+ rc=6
+ set -e
+ echo 'puppet apply exited with exit code 6'
puppet apply exited with exit code 6
+ '[' 6 '!=' 2 -a 6 '!=' 0 ']'
+ exit 6
[2018-01-30 12:32:30,415] (os-refresh-config) [ERROR] during configure phase. [Command '['dib-run-parts', '/usr/libexec/os-refresh-config/configure.d']' returned non-zero exit status 1]

[2018-01-30 12:32:30,416] (os-refresh-config) [ERROR] Aborting...
Traceback (most recent call last):
  File "", line 1, in 
  File "/usr/lib/python2.7/site-packages/instack_undercloud/undercloud.py", line 1214, in install
    _run_orc(instack_env)
  File "/usr/lib/python2.7/site-packages/instack_undercloud/undercloud.py", line 1003, in _run_orc
    _run_live_command(args, instack_env, 'os-refresh-config')
  File "/usr/lib/python2.7/site-packages/instack_undercloud/undercloud.py", line 519, in _run_live_command
    raise RuntimeError('%s failed. See log for details.' % name)
RuntimeError: os-refresh-config failed. See log for details.
Command 'instack-install-undercloud' returned non-zero exit status 1