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Joining vCenter Server to a Linked Mode group after upgrading to vCenter Server 5.0 fails with error: Instance "VMwareVCMSDS" is already in linked mode (2005930)
To resolve this issue, you can edit the ADAM database on the secondary vCenter Server so that the value linkedvc is not set.
To edit the ADAM database:
Log on to the Secondary vCenter server via RDP.
Access to the ADAM database:
For Windows 2003, click Start > Programs > ADAM > ADAM ADSI EDIT.
For Windows 2008, click Start > Administrative Tools > ADSI EDIT.
Right-click ADSI Edit at the root level and choose Connect to.
Under Connection Point, select Select or type a Distinguished name (DN) or naming context and enter:
Under Computer, select Select or type a domain or server: (Server | Domain [:port]) and enter:
Where 389 is the Port number used by the LDAP for accessing ADAM database.
On the ADSI Edit main window, expand the CN= DC=virtualcenter,DC=vmware,DC=int > OU=Licensing > OU=LicenseEntities partition.
In the right pane, select CN=<vc-guid>,OU=Licensing,LicenseEntities.
Double-click vmw-vc-InUseFeatureList, click linkedvc (in the Value column), then click Remove > OK. The value is now <not set>.
Click Apply > OK.
Note: You do not have to restart the VirtualCenter Server service.
Run the vCenter Server Linked Mode Configuration and join the secondary vCenter Sever to the primary vCenter Server in Linked Mode.
Joining vCenter Server 5.0 to older versions of vCenter Server is not supported.
For information on backing up the Adam database, see Manually backing up and restoring the vCenter Server 4.x and 5.0 ADAM instance data (1029864).
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