About Migrating a vCenter Server for Windows with an External Platform Services Controller Using the CLI

When migrating a vCenter Server for Windows that uses an external Platform Services Controller, it is converted to a vCenter Server instance with those services embedded in the appliance. For this reason, you must specify replication partner parameters in the JSON migration templates.

When migrating a vCenter Server for Windows that uses an external Platform Services Controller, you must specify replication partner parameters in the JSON migrate template. These parameters indicate if the migration is for one of the following vCenter Server and Platform Services Controller migration scenarios.

A single vCenter Server and a single Platform Services Controller instance within an SSO domain.
The first vCenter Server and Platform Services Controller instance within an SSO domain containing more than one vCenter Server.
Replicating vCenter Server and Platform Services Controller instances within an SSO domain, which you must point to an existing vCenter Server 7.0 instance as the replication partner.

Important: Before migrating a vCenter Server deployment using an external Platform Services Controller, you must first converge the external Platform Services Controller to an embedded Platform Services Controller and then perform the migration. For more information, see Removal of Platform Services Controller.

Deployments using an external Platform Services Controller are often called an MxNdeployment, where M represents the vCenter Server, and N represents the external Platform Services Controller. When representing multiple instances of vCenter Server and Platform Services Controller in a domain, this is expressed as MnxNn, where n is the number of instances. For example, M2xN2 indicates two vCenter Server instances and two Platform Services Controller instances within the same domain. When migrating such a deployment, you first migrate one instance to version 7.0, and then migrate the second instance to 7.0, specifying the first of the two instances as the replicating partner.

The replication parameters in the JSON migration template are located in the sso section of the template, and are first_instance and replication_partner_hostname.

Parameter Name	Description
`first_instance`	The `first_instance` parameter identifies the vCenter Server as either the first instance in your vCenter Server SSO domain, or as a replicating partner. If it is the first vCenter Server instance, set `first_instance` to `true` For additional instances of vCenter Server in the same SSO domain, set `first_instance` to `false`.
`replication_partner_hostname`*	If you set `first_instance` to `false`, you must specify the FQDN or IP address of a vCenter Server that has already been migrated to version 7.0, and whose external PSC has been converged into the vCenter Server appliance.

When you perform the CLI migration of a single vCenter Server for Windows instance that uses an external Platform Services Controller, the process is as follows:

Migrate the vCenter Server in your topology using the win_vc_to_vCSA_on_ESXi.json template when migrating on ESXi, or the win_vc_to_vCSA_on_VC.json template when migrating on a vCenter Server deployment.
For a deployment topology consisting of a single vCenter Server and a Platform Services Controller (an M1xN1 deployment), edit the sso section of the template such that the first_instance parameter is set to true, and remove the replication_partner_hostname parameter.
```
"sso": {
"__comments": [ This is the first instance (M1) vCenter Server management node, with "first_instance" set to "true" and "replication_partner_hostname" removed.
],
"first_instance": true
}
```
Specify the remaining configuration parameters in the JSON template, and migrate vCenter Server to version 7.0 using the CLI. See Perform a CLI Migration of vCenter Server from Windows to an Appliance.
After successfully migrating vCenter Server, decommission the Platform Services Controller. See Decommission the Platform Services Controller.
Important: Decommission the Platform Services Controller instances only after migrating and converging all vCenter Server instances in your topology.

For a deployment consisting of two or more vCenter Server and Platform Services Controller instances (an M2xN2 deployment), you first migrate the M1 vCenter Server instance to version 7.0, and then migrate the second, replicating vCenter Server instance.

Migrate the vCenter Server in your topology using the win_vc_to_vCSA_on_ESXi.json template when migrating on ESXi, or the win_vc_to_vCSA_on_VC.json template when migrating on a vCenter Server deployment.

For the first vCenter Server instance ( M1), edit the sso section of the template such that the first_instance parameter is set to true, and remove the replication_partner_hostname parameter.

"sso": {
"__comments": [ This is the first instance (M1) vCenter Server management node, with "first_instance" set to "true" and "replication_partner_hostname" removed.
],
"first_instance": true
}

For the remaining vCenter Server instance ( M2), edit the sso section of the template such that the first_instance parameter is set to false, and provide the FQDN or IP address of the vCenter Server instance to which you want to replicate the second node. The replication partner is the first vCenter Server instance ( M1) you migrated to version 7.0, which has been converged with its Platform Services Controller instance.
```
"sso": {
"__comments": [ This is the second instance (M2) vCenter Server management node, with "first_instance" set to "false" and "replication_partner_hostname" set to the hostname of the replication partner.],
"first_instance": false,
"replication_partner_hostname": "FQDN_or_IP_address"
```
Specify the remaining configuration parameters in the JSON templates, and migrate vCenter Server to version 7.0 using the CLI. See Perform a CLI Migration of vCenter Server from Windows to an Appliance.
After successfully migrating all vCenter Server instances in the topology, decommission the Platform Services Controller instances. See Decommission the Platform Services Controller.
Important: Decommission the Platform Services Controller instances only after migrating and converging all vCenter Server instances in your topology.