Adding more than on node is Federating node.
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addNode XXXX (add node to cell) with SOAP
After intall WAS ND then you can do this then u have single pnt of Admin to All Apps under multiple nodes.
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This refers to adding a Node to a Websphere cell.
A node is a collection of application server instances.
A cell is a collection of nodes.
To federate the node you must use the addNode command or add it from the nodes section of the admin console under The system administration section on the left nav pane.
To create a managed node use the Profile Managment tool.
The cell to which the node must be federated must have the deployment manager running at time of federation.
Refer to IBM info Centre for more info on Websphere Application Server.

3 Users have rated as useful.
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sateesh babu Ginjupalli
Answered On : May 15th, 2012
Federation is nothing but addition.Federating the node means we have to add the node of the standalone application server to the DMGR profile.
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megha
Answered On : Sep 5th, 2012
Federating node means adding stand alone application or stand alone profile to deployment manager(DMGR), we can achieve this by using admin console or addnode command of stand alone profile.
CMD: ./addNode.sh
Once this process is successfully done, one nodeagent server is created for app server, this nodeagent is responsible for communication between dmgr and application server.
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preethi
Answered On : Nov 11th, 2012
Federation : It is the process of integrating a stand alone application server to Dmgr..Now the admin console of the stand alone server vanishes and is controlled from Dmgr admin console.
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chandrasekhar
Answered On : Apr 10th, 2013
giving the control of application server profile to dmgr is nothing but federation. for single point of administration we are doing federation.we can do federation in 2 ways.1.from admin console of dmgr(by adding the soap port number of asp in ) and 2.from command prompt of application server(the soap port number of dmgr) by using add node command.
changes after federation:
node agent will be activated in asp
node copy of asp will be copied into cell of dmgr
admin condole of asp will be deactivated.
pre requests for federation:
both servers should be in running position
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