Affects Version/s: 6.2.10 EE GA1, 6.2.X EE, 7.0.0 Alpha 1, 7.0.0 Alpha 2
When the process of master node hangs for a while, another node becomes the master. Later, if the process of the original master node resumes, there will be two master nodes.
Steps to reproduce:
- Install two Tomcat bundles.
- Use the following simple portal-ext.properties for configuring basic clustering:
- Start the nodes consecutively.
- Run the following Groovy script in the nodes' Server Administration --> Script tab:
You get master node?true on master and master node?false on the other node.
- Create heap dump from the first node using the command. (<JVM_PID> means the process id of Node 1 JVM.) This will make the process hang for a while.
- Run the Groovy script again on both nodes.
Result: Both nodes return master node?true.
Expected result: One node returns master node?true and the other returns master node?false.
Alternative ways for suspending a process:
Suspend the process identifiedy by PID:
Resume suspended process identifiedy by PID:
On windows you can suspend a process by using the Resource Monitor. (See screenshots pause1.png and pause2.png.)
Also VisualVM might be useful to figure out which Java process you should suspend.