Solution 1

Check if the WebLogic server host is able to connect to Applications Manager as we connect in the browser. i.e.  http://<ApplicationsManager hostname>:<portNumber> should be reachable. 

Also check whether any errors or exceptions are thrown in the WebLogic logs.

Solution 2

For WebLogic versions 10.x , 11g and below Applications Manager deploys an MBean agent ( AdventNet_Agent:Name=WLSDCMBean)  to WebLogic server. This agent then collects data from WebLogic server and sends data back to Applications Manager. Due to any of the below reason, the auto deployment of agent fails :

1. Applications Manager machine is not accessible from WebLogic machine.
   
2. Applications Manager port is not accessible from WebLogic machine.
   
3. "Creation of MLet MBeans is not allowed based on the weblogic.management.ManagementAppletCreateEnabled system property value" error. For versions 11g and above, creation of MBeans via MLet is not allowed by default.
   

1. Deploy the attached registermbeans.war file to WebLogic server.
   
2. Restart WebLogic
   
3. Restart Applications Manager
   
4. The data collection will start after this.
   

Solution 3

If you are using our Free Edition, try restarting your WebLogic instance and ensure that Applications Manager collects data before the limit of 5 connections is reached. 

Note:

1. Applications Manager webserver port (eg., 9090) should be accessible from the WebLogic server. And the HTTP Port of WebLogic server (eg., 7001) should be accessible from the Applications Manager server(i.e telnet).

2. Applications Manager does a jndi lookup to get the Mbeanserver. Check if the configured user has the permission to do a jndi lookup. This can be checked as follows:

· Access the JNDI Tree security policy from WebLogic Admin console.

· Admin console--> Environment-->Servers-->(Select the server)-->View JNDI Tree-->Security-->Policies-->Methods. Under Methods, select ALL.

3. Confirm if the ListenAddress configured in the WebLogic server is same as the one used for configuring WebLogic monitor in Applications Manager.

4. Check if the /etc/resolv.conf file (in windows it is \etc\hosts file) in the machine running Applications Manager has the correct domain, search, nameserver list defined for the WebLogic server host.