Oracle VM: Timeout starting OVMM service

I encountered this problem a while ago during a VM Manager restart: OVMM service didn't started anymore going in timeout.
As a general suggestion when this happens first thing to do is to have a look at VM Manager logs, located at:

/u01/app/oracle/ovm-manager-3/machine1/base_adf_domain/servers/AdminServer/logs/AdminServer.log

if file is too long to read you could just give a try grepping only errors

cat /u01/app/oracle/ovm-manager-3/machine1/base_adf_domain/servers/AdminServer/logs/AdminServer.log | grep ERROR

In this case however OVMM Timeout was caused by an issue in /etc/init.d/ovmm file and in detail by this line:

nohup su - oracle -c "$USER_MEM_ARGS DOMAIN_PRODUCTION_MODE=true JAVA_OPTIONS=\"-Djava.awt.headless=true -Xdebug -Xrunjdwp:transport=dt_socket,address=127.0.0.1:8453,server=y,suspend=n -da:org.apache.myfaces.trinidad\" /u01/app/oracle/ovm-manager-3/machine1/base_adf_domain/startWebLogic.sh &" > /dev/null

As you can see by default ovmm start script starts WebLogic server as oracle user, instead of root user, the one used to perform VM Manager installation.
I just fixed it by simply swapping oracle user with root user, this happened despite before VM Manager installation I launched "createOracle.sh" script which performs oracle user creation and permissions assignment.

So, to solve this issue simply replace:

nohup su - oracle -c "$USER_MEM_ARGS DOMAIN_PRODUCTION_MODE=true JAVA_OPTIONS=\"-Djava.awt.headless=true -Xdebug -Xrunjdwp:transport=dt_socket,address=127.0.0.1:8453,server=y,suspend=n -da:org.apache.myfaces.trinidad\" /u01/app/oracle/ovm-manager-3/machine1/base_adf_domain/startWebLogic.sh &" > /dev/null

with:

nohup su - root -c "$USER_MEM_ARGS DOMAIN_PRODUCTION_MODE=true JAVA_OPTIONS=\"-Djava.awt.headless=true -Xdebug -Xrunjdwp:transport=dt_socket,address=127.0.0.1:8453,server=y,suspend=n -da:org.apache.myfaces.trinidad\" /u01/app/oracle/ovm-manager-3/machine1/base_adf_domain/startWebLogic.sh &" > /dev/null


Then start ovmm service again:

service ovmm start

That's all!!