Comment 7 for bug 1665669

Verified on 9.2 + mu1 updates.

Steps to verify:
scenario 1:
1) reboot of controller (sudo reboot)
2) ssh to controller, check UMM_DRC value
3) virsh destroy fuel_custom_slave-01
   virsh start fuel_custom_slave-01
4) ssh to controller, check UMM_DRC value, umm status
5) waiting for 15 min
6) check UMM_DRC value
7) virsh destroy fuel_custom_slave-01
   virsh start fuel_custom_slave-01
8) ssh to controller, check UMM_DRC value, umm status

scenario 2:
1) reboot of controller (sudo reboot)
2) ssh to controller, check UMM_DRC value
3) waiting for 15 min
4) ssh to controller, check UMM_DRC value
5) virsh destroy fuel_custom_slave-01
   virsh start fuel_custom_slave-01
6) ssh to controller, check UMM_DRC value, umm status
7) waiting for 15 min
8) check UMM_DRC value
9) virsh destroy fuel_custom_slave-01
   virsh start fuel_custom_slave-01
10) ssh to controller, check UMM_DRC value, umm status

Actual results after the fix:
scenario 1:
2) root@node-1:~# cat /var/lib/umm/*
   UMM_DRC=1
4) root@node-1:~# cat /var/lib/umm/*
   UMM_DRC=2
   root@node-1:~# umm status
   runlevel N 2
6) root@node-1:~# cat /var/lib/umm/*
   cat: /var/lib/umm/*: No such file or directory
8) root@node-1:~# cat /var/lib/umm/*
   UMM_DRC=1
   root@node-1:~# umm status
   runlevel N 2

scenario 2:
2) root@node-1:~# cat /var/lib/umm/*
   UMM_DRC=1
4) root@node-1:~# cat /var/lib/umm/*
   cat: /var/lib/umm/*: No such file or directory
6) root@node-1:~# cat /var/lib/umm/*
   UMM_DRC=1
   root@node-1:~# umm status
   runlevel N 2
8) root@node-1:~# cat /var/lib/umm/*
   cat: /var/lib/umm/*: No such file or directory
10)root@node-1:~# cat /var/lib/umm/*
   UMM_DRC=1
   root@node-1:~# umm status
   runlevel N 2

Sometimes UMM_DRC counter doesn't increase value after virsh destroy/start - separate bug was created to track this issue - https://bugs.launchpad.net/fuel/+bug/1671827.