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Migrating infrastructure from VMware to OpenStack is a strategic step toward modernization that significantly reduces operating costs. Atman provides support throughout the migration process with the advanced OS Migrate tool, which ensures a secure transfer of virtual machines without risking data loss.

For the migration to take place, the VMware platform must meet certain conditions.

vSphere 6.5 or higher is required, as well as access to vCenter Server for central management.

Virtual machines should have one of the following operating systems installed, in the specified version or higher:

• Linux CentOS 7
• Ubuntu 18.04
• Windows Server 2016.

Uninterrupted network connectivity between the VMware and OpenStack environments is required, as well as sufficient datastore space to create and store temporary snapshots.

It is also important to configure access permissions correctly. The service user whose account will be used during migration must have permissions to read metadata, manage snapshots, and access the datastore.

On the OpenStack platform, sufficient resource limits (quotas) must be in place to support the migrated environment. These quotas should be at least as large as the environment itself. The support team will explain all of this in detail during the migration planning stage.

We have developed a list of tasks that the customer should complete in the OpenStack environment before the Atman team proceeds with the virtual machine migration.

For the migration to run smoothly and successfully, critical issues must be addressed.

• Mapping allocated computing resources by selecting appropriate virtual machine configurations (defining the number of virtual processors and GB of RAM) in the new environment based on the original environment’s configurations.

• Recreating networks, routers, and security groups, along with their rules, is a task that the customer must perform before starting the migration. For complex environments, an “infrastructure as code” (IaC) tool, such as Terraform or Ansible, can speed up this process.

•  Installing the appropriate drivers on virtual machines (with Windows) will help avoid problems with running machines in the new environment and network communication issues after migration.

Atman manages the entire migration process from VMware to OpenStack, which consists of three phases:

1. Discovery Phase

During this phase, we take an inventory of the vCenter environment and collect metadata about vCPUs, RAM, disks, and network adapters, as well as their sizes. These activities do not disrupt the VMware environment.

2. Pre-Migration Phase

During this phase, we ensure that the OpenStack environment is ready for migration and can accept transferred resources. Then, we create the network topology with communication rules, set up a network connection between the environments, and open the appropriate ports. Most importantly, we create a conversion server – a virtual machine in the OpenStack environment responsible for mapping and copying resources from VMware to OpenStack.

3. Migration Phase

The process of transferring resources from the original environment to the target environment takes place at this stage. This includes disk format conversion, network driver changes, virtual machine configuration, network creation, and proper port configuration, with the option to preserve existing MAC addresses.

During the migration process, Atman uses the aforementioned OS Migrate tool and, in particular, the NBDKit module. An essential element of the process is the application of rules developed based on experience gained by Atman during previous migrations.

Migrating data from volumes connected to virtual machines requires two brief interruptions to the operation of machines in the VMware environment to ensure security and data consistency.

The first interruption is necessary when taking machine snapshots and copying data to the OpenStack cloud environment. The second interruption occurs at the final stage of environment migration, i.e., when closing it on the VMware side. After shutting down the virtual machine, we synchronize any additional data that has appeared since the snapshot was taken.

After completing this final synchronization, we start the machines in the new OpenStack environment. The original VMware environment can then be deleted.

Atman engineers support the customer at every stage of migration – from analyzing the existing VMware environment, through preparing the OpenStack infrastructure and configuring OS Migrate, to full production migration.

We test a selected subset of VMs, monitor the migration process, and validate all migrated machines with the customer.

Before the migration process begins, we train the customer’s team in OpenStack platform management.

Migrating to OpenStack generates significant savings. The main financial benefit is eliminating VMware licensing costs.

The OpenStack platform enables more efficient use of hardware resources and flexible customization, further reducing the cost of virtual resources.

Additionally, transparent open source technology increases the cloud’s independence and security.

With Atman’s support, migrating from VMware to OpenStack is a safe and convenient way to modernize your infrastructure, gain full control over your cloud platform, and achieve significant financial savings. Contact our team to learn more about the service.