14 October, 2020
At the end of this chapter you will be able to:
The following sections describe general procedures that are applicable to both the Java and scripted version of Node Manager:
Node Manager must run on each computer that hosts a WebLogic Server instance. Configure each computer as a machine resource in WebLogic Server, and assign each server instance that you will control with Node Manager to the machine upon which it runs.
Ideally, Node Manager should run as an operating system service or daemon, so that it is automatically restarted in the event of system failure or reboot.
Node Manager is ready-to-run after WebLogic Server installation if you run Node Manager and the Administration Server on the same machine and use the demonstration SSL configuration.
By default, the following behaviors are configured:
However, by default, the nmConnect command cannot be used in a production environment. You must first perform the following procedures to use nmConnect in a production environment.
1. Start the Administration Server.
2. Using the Administration Console update the Node Manager credentials from the Advanced options under domain_name→Security→General.
3. Invoke WLST and connect to an Administration Server using the connect command.
4. Run nmEnroll using the following syntax: nmEnroll([domainDir], [nmHome])
Running nmEnroll() ensures that the correct Node Manager user and password token are supplied to each Managed Server. Once these are available for each Managed Server, you can use nmConnect() in a production environment.
Note: You must run nmEnroll() on each machine that is running a Managed Server. Additionally, you should run nmEnroll() for each domain directory on each machine.
The nm_password.properties file contains the Node Manager username and password. These are used to authenticate the connection between a client (for example, the Administration Server) and Node Manager.
Note: This username and password are only used to authenticate connections between Node Manager and clients. They are independent of the server admin ID and password.
Administration Console NM Security
Domain_Name -> Security -> Advanced Options
Configure a machine definition for each machine that runs a Node Manager process using the Environment→Machines→<machine_name>→Node Manager page in the Administration Console. Enter the DNS name or IP address upon which Node Manager listens in the Listen Address field.
In the Administration Console, on the Server→Configuration→Server Start page for the Managed Server, specify the startup arguments that Node Manager will use to start a Managed Server. If you do not specify startup arguments for a Managed Server, Node Manager uses its own properties as defaults to start the Managed Server.
You can use the Node Manager to set the startup properties for a server. These properties can be defined in startup.properties or passed as an object using administrative utilities such as WLST. This file is defined for each server instance and is located in:
Node Manager requires you to set several environment variables before you start it. You can set these variables manually on the command line, or you can create a start script that sets them automatically. The sample start scripts provided with WebLogic Server, startNodeManager.cmd, and startNodeManager.sh, set the required variables.
The directory WL_HOMEserverbin (where WL_HOME is the top-level directory for the WebLogic Server installation) contains uninstallNodeMgrSvc.cmd, a script for uninstalling the Node Manager service, and installNodeMgrSvc.cmd, a script for installing Node Manager as a service.
Node Manager credentials are located on the domain_name→Security→General→Advanced Options page in the Administration Console.
Administration Console users do not need to provide credentials to connect to Node Manager explicitly—the Node Manager username and password are available in the domain configuration and are provided automatically.
Remote Server Start Security for Java-Based Node Manager
Credentials for Managed Servers and Administration Servers are handled differently:
Node Manager properties define a variety of configuration settings for a Java-based Node Manager process. You can specify Node Manager properties on the command line or define them in the nodemanager.properties file, which is created in the directory where you start Node Manager the first time it starts up after installation of WebLogic Server. Values supplied on the command line override the values in nodemanager.properties.
nodemanager.properties is created in the directory specified in NodeManagerHome, where NodeManagerHome is WL_HOME/common/nodemanager. If NodeManagerHome is not defined, nodemanager.properties is created in the current directory.
Each time you start Node Manager, it looks for nodemanager.properties on the current directory and creates the file if it does not exist in that directory. You cannot access the file until Node Manager has started up once.
If you have a domain that has Managed Servers on multiple physical machines, you must ensure that the Node Manager is installed and configured on each machine. You can use the WLST command nmEnroll to copy all of the required domain and configuration information from one machine to another.
When configuring Node Manager to run as an inetd or xinetd service, the following considerations apply:
The following example shows how the Node Manager can be configured within xinetd:
# default: off
# description:nodemanager as a service
type = UNLISTED
disable = no
socket_type = stream
protocol = tcp
wait = yes
user = <username>
port = 5556
flags = NOLIBWRAP
log_on_success += DURATION HOST USERID
server = <path-to-jave>/java
env = CLASSPATH=<cp> LD_LIBRARY_PATH=<ldpath>
server_args = -client -DNodeManagerHome=<NMHome> <java options> <nodemanager options> weblogic.NodeManager -v
– Using SSL With Script-based Node Manager
– Creating a Node Manager User
– Configuring Script-based Node Manager Security
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