11th May 2023

So I have in the past talked about my experiences with manual migration of Virtual Machines to OCI . I have talked about the Oracle Cloud VMware Solution which is a Customer managed VMware solution that can be used to easily migrate VMware vms from on premise or any SDDC to an SDDC hosted in Oracle Cloud using HCX.

The Oracle Cloud Migrations Service  is a service from Oracle that automates and improves on the manual migration process. It enables VMware Change tracking based incremental VMDK updates, it is agent based so you need to deploy an agent in your on Premise VMware SDDC .

It is a pretty new service  as it was launched in October of 2022 and we are still evaluating this but we intend to use this in several large projects with Multiple hundred VMs in the very near future. The interesting feature is that it can migrate from VMware VMs directly to OCI Compute instances , i.e moving the VMs directly to OCI compute instances. 

The documentation is quite comprehensive  It also has integrations with the OCI CLI  using the oci cloud-migrations set of commands.

As you can see the steps that are laid out in order to Migrate from Vmsphere 6.5 , 6.7 or 7.0 to OCI are as follows.  You need to create an Oracle Cloud Migration setup from OCI 

So the first step is to create an Inventory. When we go to do this we need to deploy the agent .

Once the Inventory is created we are presented with a step by step guided approach in order to start our process of Migration

We need to create the remote connection , link to our discovery agent and discover the resources in order to populate the Inventory. Afte this we can setup Migration projects, Migration plans and replication schedules in order to replicate the VMs from the source SDDC to the native OCi vms. Please note that you still need to ensure that the prerequisites are fulfilled for a native migation such as installation of the Oracle virtio drivers especially for the Unsupported Operating systems. the process is clearly outlined in the documentation but if you are just skimming through you might miss this requirement.

The following are the related IAM policy statements for the Migration Admins

Allow group <USER-GROUP> to manage ocm-migration in compartment <COMPARTMENT-NAME>

Allow group <USER-GROUP> to manage ocm-migration-asset in compartment <COMPARTMENT-NAME>

Allow group <USER-GROUP> to manage ocm-migration-plan in compartment <COMPARTMENT-NAME>

Allow group <USER-GROUP> to manage ocm-target-asset in compartment <COMPARTMENT-NAME>

Allow group <USER-GROUP> to manage ocm-replication-task in compartment <COMPARTMENT-NAME>

Allow group <USER-GROUP> to manage ocm-connector in compartment <COMPARTMENT-NAME>

Allow group <USER-GROUP> to manage ocm-replication-schedule in compartment <COMPARTMENT-NAME>

Apart from this several service policies need to be set up for the migration service and for the remote agent.

As you can see we can download the agent from the created Source environment screen and deploy the same in our SDDC. This can be used to discover the resources and assets in the on premise SDDC.

After this we proceed by Discovering the assets.

Once assets are discovered we need to setup a Migration project and one or more migration plans for the migration

We can directly go for creation of the Project with Plan and we can add the discovered assets to the migration plan.

The Migration plan can be used to do the initial replication followed by Subsequent Incremental Transfers. Replication buckets are needed in object storage to store the blocks and the changes. Block change tracking needs to be enabled in the source SDDC in order to support the incremental transfers

A hydration agent is required in the target compartment to help rehydrate the block volumes with the changes that are in the replication buckets.

As I mentioned earlier the migrated VM does require certain OCI specific drivers and this can be automatically enabled for certain operating system types see this section "Boot Volume Modifications for Migration" This also outlines the manual install method in case you need to do this pre -migration.

As you can see this service not only does a lot more than the Manual method including multiple VMDK migration and Incremental Transfers it also enabled bulk migration and scheduled Migration. It definitely is a new and useful tool in the arsenal of the OCI migration Expert.