WebLogic – Error starting managed server from Console : Node Manager associated with this machine is not reachable

This post cover steps on where to look for issues related to starting Managed Server via WebLogic Console.

If you are new to WebLogic then first go through WebLogic Domain, Administration Server and Managed Server here , start/stop in Weblogic Server here and Node Manager in WebLogic here

How to start Managed Server via WebLogic Console (/console application running on Administration Server) ?

  • Login to console http://hostname.domainname:admin_port/console
  • Environment -> Servers -> click on tab Control -> select Managed Server which you wish to start -> click on button Start

Prereq for Managed Server to start via Console ?
Start Node Manager ($WL_HOME/server/bin/startNodeManager.sh)
2. Configure Machine and verify NodeManager details (Listen Address and Port) ; Environment -> Machines -> Configuration -> Node  Manager



3. Attach Managed Server to Machine : Environment -> Servers -> [select managed server] -> under General tab Configuration , select machine

4. Add domain loaction in $WL_HOME/common/nodemanager/nodemanager.domains
entry like

5. Restart Node Manager and try starting Managed Server from Console


Error Message

If you hit errors starting Managed Server (in WebLogic) from console like
For Server name_of_managed_server],  the Node Manager associated with machine [Machine_Name] is not reachable ” then here is step to troubleshoot

1. Check if Machine is configured against Node where Managed Server is running. (via console)
2. Check Node Manager IP and port number configured for that Machine (via console)
3. Check if Node Manager is running on that machine on that port (netstat -an | grep [port_number])
4. If Administration Server and Managed server are on different machine and if there is firewall between two machines then check Node Manager port is open across firewall
5. Check Node Manager log file for any errors
6. Check if there is any issue with SSL certificate (Administration Server communicates with NodeManager via SSL) : Disable hostname verification if this is an issue (or recreate certificate)
In my case there was error in Node Manager log file

12-Mar-2010 17:35:17 weblogic.nodemanager.server.NMServer main
SEVERE: Fatal error in node manager server
java. lang. Class Cast Exception: sun.nio.ch. InheritedChannel $InheritedSocketChannel
at weblogic.nodemanager.server.Listener.<init>(Listener.java:42)
at weblogic.nodemanager.server.SSLListener.<init>(SSLListener.java:32)
at weblogic.nodemanager.server.NMServer.start(NMServer.java:200)
at weblogic.nodemanager.server.NMServer.main(NMServer.java:355)
at weblogic.NodeManager.main(NodeManager.java:31)

Have you seen this issue in your Node Manager setup (I am using JRockit on Sun Solaris 10 Sparc 64 bit and Node Manager shipped with FMW Binary) ?

Can you help me in fixing this issue ?

Did you get a chance to download Free Interview Questions related to WebLogic? If not, download it here http://k21academy.com/weblogic-interview-question


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About the Author Atul Kumar

Oracle ACE, Author, Speaker and Founder of K21 Technologies & K21 Academy : Specialising in Design, Implement, and Trainings.

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