If you have old MediaAgent in cluster environment, after successful migration of libraries, and test of backups and restores, add the new MediaAgent computer to cluster group client.
Procedure
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From the CommCell Browser, navigate to Client Computer.
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Right-click the <Cluster Group Client>, and then click Properties.
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On the Client Computer Properties dialog box, click Advanced.
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On the Advanced Client Properties dialog box, click the Cluster Group Configuration tab.
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In the Available list, select the new MediaAgent, and then click Add.
The new MediaAgent that you selected move to the Selected list.
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In the Selected list, select the old MediaAgent, and then click Remove.
The old MediaAgent that you selected move to the Available list.
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Click OK.
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Click OK.
A message appears that tells you that cluster group configuration was saved successfully.
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Click OK.