Manage node agents
Overview
Node agents are administrative agents that represent a node to your system and manage the servers on that node. Node agents monitor appservers on a host system and route administrative requests to servers.
Before you can manage a node agent, install the ND product.
If you plan to change the system clock, stop...
- appservers
- node agent servers
- deployment manager server
Once you stop the servers, change the system clock, and then restart the servers. If you change the system clock on one system, ensure the clocks on all systems that communicate with each other and have WAS installed are synchronized. Otherwise, you might experience issues, such as security tokens no longer being valid.
A node agent is a server that is created automatically when a node is added to a cell. A node agent runs on every host computer system that participates in the ND product. You can view information about a node agent, stop and start the processing of a node agent, stop and restart appservers on the node that is managed by the node agent, and so on.
A node agent is purely an administrative agent and is not involved in application serving functions. A node agent also hosts other important administrative functions, such as file transfer services, configuration synchronization, and performance monitoring.
You can manage nodes through the wsadmin scripting tool, through the Java APIs, or through the console. Perform the following tasks to manage nodes on an appserver through the console.
Procedure
- View information about a node agent. Click System Administration > Node Agents in the console navigation tree. To view additional information about a particular node agent or to further configure a node agent, click the node agent name under Name.
IP verions: Both IPv4 and Internet Protocol V6 (IPv6) are now supported by WAS, but there are restrictions that apply to using both IPv4 and IPv6 in the same cell. Note that when a node is added to a cell, the format in which the name is specified is based on the version of IP the node will be using. See IP version considerations for cells.
- Stop and then restart the processing of a node agent. On the Node Agents page, select the check box beside the node agent to restart; then click Restart. It is important to keep a node agent running because a node agent must be running for appservers on the node managed by the node agent to run.
- Stop and then restart all of the appservers on the node that is managed by the node agent. On the Node Agents page, select the check box beside the node agent that manages the node with servers to restart, and click Restart all Servers on Node.
The node agent for the node must be processing to restart appservers on the node.
- Stop the processing of a node agent. On the Node Agents page, select the check box beside the node agent to stop processing; click Stop.
Results
Depending on the steps that you completed, you have viewed information about a node agent, stopped and started the processing of a node agent, and stopped and restarted appservers on the node that is managed by the node agent.
What to do next
You can administer other aspects of the ND environment, such as the deployment manager, nodes, and cells.
Node agent collection
Related tasks
Running an Application Server and node agent from a non-root user
Running an appserver from a non-root user and the node agent from root
Considering security specific to a multi-node or process ND environment