Oracle Enterprise Manager / Cloud Control

Environment Overview
To show info about currently running OMS including URLS, ports, and paths:

cd $OMS_HOME/bin
./emctl status oms -details

Reset Weblogic Admin Password
12c , 13c Cloud Control: Steps for Modifying the Password for Weblogic and Nodemanager User Accounts in the Enterprise Manager Installation (Doc ID 1450798.1)
Reset Weblogic Admin Server Password
Querying the Management Repository

EMCLI Command Line Automation

Agent Troubleshooting
Interactive config refresh failing
I found the interacive screens to refresh a host config did not always work. This includes using the "Refresh Configuration" button on the host screen or the Enterprise-Configuration-Refresh_Host_Configuration to kick off a configuration refresh job. From the affected agent home run:

./emctl control agent runcollection ll_host_config 

If all is good you will get a "EMD runCollection completed successfully" message returned.
Discovering new Oracle Homes
Discover and promote Oracle Homes as Targets