Eventhough if you didn't give the cluster name. it will still work with the existing CMS name.
Please check the below document for the defining the cluster name
below is the content of the above url. Let me know if you need any additional details.
change the cluster name on Windows:
Use the CCM to stop any SIA that is a member of the cluster.
Click SIA Properties on the toolbar.
Click the Configuration tab.
Select the Change Cluster Name to check box.
Type the new name for the cluster.
But the cluster name is prefixed by the @ symbol.
For instance, if your existing CMS is called PROD1, then the default cluster name is @BI-PROD
Click OK and then start the Central Management Server.
The CMS cluster name is now changed. All other CMS cluster members are dynamically notified of the new cluster name (although it may take several minutes for your changes to propagate across cluster members).
Go to the Servers management area of the CMC and check that all of your servers remain enabled. If necessary, enable any servers that have been disabled by your changes
Update Cluster Name in Web Applications:
Cluster name is defined in the BO, now we have to update the same in the Business Intelligence 4.0 web applications (Netweaver, Websphere, Tomcat, Weblogic, JBOSS)
If you have added additional CMSs to your deployment, and you are using a Java application server, you must modify the PlatformServices.properties file in the webapps/BOE/WEB-INF/config/custom directory of your web application deployment.
To define cluster properties for the BOE web application :
1.Access the custom folder for the BOE.war file on the computer hosting the web applications.
If you are using the Tomcat web application server installed with SAP BusinessObjects Business Intelligence platform, you can access the following folder:
C:Program Files (x86)/SAP BusinessObjects/Tomcat6/webapps/BOE/WEB-INF/config/custom
Tip:
If you are using a web application server that does not enable direct access to the deployed web applications, you can use the following folder in your product installation to modify the BOE.war file.
<INSTALLDIR>SAP BusinessObjects /Business Intelligence platform 4.0/warfiles/webapps/BOE/WEB-INF/config/custom.
You will have to later redeploy the modified BOE.war file.
2.Create a new file.Use Notepad or any other text editing utility.
3. Specify CMC cluster properties for each cluster in your deployment.
Precede each cluster name with an @ symbol, and separate each CMS name with a comma (,).
The port number is separated from the CMS name with a colon (:). The port number is assumed to be 6400 unless it is specified.
Use the cms.clusters property to specify each cluster in your deployment. For example,
cms.clusters=@samplecluster,@samplecluster2, @samplecluster3. Use the
cms.clusters.[cluster name] property to specify each CMS in the cluster. For example:
cms.clusters=@samplecluster,@samplecluster2, @samplecluster3
cms.clusters.samplecluster=cmsone:6400,cmstwo
cms.clusters.samplecluster2=cms3,cms4, cms5
cms.clusters.samplecluster3=aps05
Below is the example:
cms.clusters=@BI-PROD
cms.clusters.BI-PROD=BXY.PROD1.XYZ.COM:6400, BXY.PROD2.XYZ.COM:6400, BXY.PROD3.XYZ.COM:6400, BXY.PROD4.XYZ.COM:6400
Make sure that there are no syntax issues.
4. Save the file with the PlatformServices.properties name.
5. Restart the web application server.
If you create the PlatformServices.properties file in the war files (i.e C:\Program Files (x86)\SAP BusinessObjects\SAP BusinessObjects Enterprise XI 4.0\warfiles\webapps\BOE\WEB-INF\config\custom). You need to redeploy the BOE webapps.
The new properties take affect only after the modified BOE web application is redeployed on the computer running the web application server. Use WDeploy to redeploy the WAR file on the web application server.
For more information on using WDeploy, see the SAP BusinessObjects Business Intelligence Platform Web Application Deployment Guide.
Once you complete the activity and update your cluster name in BI Launchpad properties and Opendocument properties to reflect in the login screens.