You may get the following error while adding a Secondary host to an RDS:

Error occurred on host <HOSTNAME>. Replica link for the same
 remote host already exists.

When trying to add the Secondary host to the RDS you may sometimes get the above error, if there is an RLINK already associated with the Primary RVG of the RDS and having the remote host field the same as the host, which you want to add as a Secondary. It could also occur if you try to associate an existing RLINK using the Command Line Interface. To check this run the command vxprint -l <rvgName> command on Primary where <rvgName> refers to the name of the Primary RVG of the RDS. In the command output display, you see an RLINK which has the remote_host field that is set to the Secondary host which is the same one that you want to add as Secondary.

To solve this problem, at the command prompt of the host for which the error was displayed, run the following command:

vxprint -l <rvg>

This command displays the RLINKs associated to the specific RVG. Identify the RLINK for the host that you try to add as Secondary using the information in the field remote_host. For this RLINK run the command vxrlink -f rm <rlink>

Now you can add the Secondary or associate the RLINK.