Enhanced-Linked Mode enables you to view all your vCenters from one console. I wanted to document how to do this and how simple in 6.7 update 1 and how easy it is. My setup is pretty simple, I have 2 vcenters servers vcenter01.demo.lan and vcenter02.demo.lan. Both are in their own SSO domain called vsphere.local.
Enough of that, lets get into it.
Step 1.
SSH into the the vcenter host you want to join.
Step 2.
At the prompt we want to run the following pre-check command
cmsso-util domain-repoint --mode pre-check --src-emb-admin administrator --replication-partner-fqdn vcenter01.demo.lan --replication-partner-admin administrator --dest-domain-name vsphere.local
Once you run this command you will get an output if it succeeds or not. You will also see the path to the log files. It is suggested to view the files and verify that you do not have conflicts

Step 3.
Once you have reviewed the result run the following command to do the actual re-point. Please note that once you have done the re-point you will need to re-register any plugins with the vCenter
cmsso-util domain-repoint --mode execute --src-emb-admin administrator --replication-partner-fqdn vcenter01.demo.lan --replication-partner-admin administrator --dest-domain-name vsphere.local

Step 4.
Verify the the other host is a replication partner.
/usr/lib/vmware-vmdir/bin/vdcrepadmin -f showpartners -h localhost -u administrator -w PASSWORD
You will get the following output.

Once you have completed the above steps you will be able to view all your vCenters from one console.