This is my report on configuring vCenter Linked Mode. It meant trouble for me, because vCenter was installed using the simple install it was not possible to link two of them together. I didn't know this, so I had to reinstall both vCenters and reinstall while configuring SSO for a multisite environment. If you already did that, linking vCenters together is quite easy.

• Log on to secondary vCenter (recovery site in terms of SRM)
• Go to Start → All Programs → VMware → vCenter Server Linked Mode Configuration (Run as Administrator)

This will start the vCenter Server Linked Mode wizard:

Select Modify Linked Mode configuration:

Check the Join vCenter server instance to an existing Linked Mode group or another instance:

You'll receive a warning regarding vCenter version support, which is also stated in the best practice:

Enter the primary vCenter FQDN, and keep the port default unless you've changed it during the installation of vCenter:

Then I got this error:

Which had this error in the logfile mentioned:

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Operation "Join instance VMwareVCMSDS" failed:
Action: Join Instance
Action: Prepare for Join
Problem: Remote VC's vcenter.shift.local SSO domain ID is does not match.


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Recovering from failed Operation "Join instance VMwareVCMSDS"

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Recovery successful

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Execution error.

According to http://communities.vmware.com/thread/420746?start=15&tstart=0 this is due to installing SSO using the simple installation method. SSO need to be installed as multisite (high availability) which is not possible using the simple install.

After reinstalling SSO I tried it again and it went successful without any problem, leaving me with this view in vCenter: