12c SOA Weblogic - Node Manager is inactive or unreachable

Node Manager is inactive or unreachable

Problem description:  

Sometimes Node manager Status is showing Inactive and shows below error:    

weblogic.nodemanager.NMConnectException

Solution:

Step1: 

Shutdown all the servers and Admin from admin console.

Step2: 

Go to unix/AIX box and to DOMAIN_HOME/bin folder and run nodemanager.sh in both nodes(if its clustered).

nohup startNodeManager.sh &

Step3:
Start the admin server 

go to DOMAIN_HOME/bin folder  and run the following command.

nohup ./startWebLogic.sh > /dev/null 2>&1&

Step4: 

Go to Admin console and check  Domain>>Environment>>Machines>>click on one machine >>Go to Monitoring Tab and check status. It should be reachable now.