Thursday, December 9, 2010

How to start a Node Agent using scripting?

This is a tricky question.  The quick answer is that it can't be done using the typical wsadmin commands.  But it can be done by 'shelling out' from your python script to issue an operating system command.

My colleague and fellow wsadmin contributor Jose Luis provided this Q&A dialog...


1) Is it possible to start the Node agent using wsadmin scripting?

No.

You can not do any operations on a Node agent if it is down. A Node agent must be running in order to work with it.

2) Why don't wsadminlin.py methods such as 'startServer' and 'isServerRunning' work for Node agents?

The job of the node agent is to start and stop servers, and to monitor them.  Under the covers, the wsadmin startServer command asks a running node agent to start servers.  But the node agent can not start itself.  Therefore the 'startServer' command can not start a node agent.

However, method 'isServerRunning' does work on Node agents. It returns True if the node agent is running and False if it is down.

3) How do I start a Node agent that is not running?