If you are getting above error in Weblogic 12c, chances are you are trying to start NodeManager from $WLS_HOME/server/bin/startNodeManager.sh
Node Manager configuration options and other things have been changed and expanded in 12c as compared to 11g. I will to cover the differences in my another blog.
In Weblogic 12c, we have to start the node manager from $DOMAIN_HOME/bin using the startNodeManager.sh script.
So, to resolve above issue, start NodeManager using