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IT migration is a little like moving house: if you prepare carefully, a lot of the pitfalls can be avoided. That’s why we’ve provided a comprehensive guide to successful VMware migration. It is aimed at enterprises and IT professionals who wish to transfer their existing infrastructures to a VMware environment.
We detail the necessary steps, available methods, potential difficulties and best practices to ensure a smooth and efficient migration.

Free Ebook

How do you respond to rising VMware costs?

Based on our experience of working with a number of companies, we have summarized the changes that have taken place, who is being affected, and what the alternatives might be so that we can provide you with informed strategic advice.

Summary

What is migration?

Migration involves moving a virtual machine (VM) to a new host or storage location.The VM can be moved from one computing resource or storage location to another and the migration can take place either with or without interruptions to service.

Migration should not be confused with:

  • Moving a VM from one inventory folder to a different folder or resource pool in the same data centre.
  • Cloning a VM or copying its virtual disks and configuration file to the same vCenter Server system.
  • Cloning and copying a VM in the same vCenter Server system.

Why should you migrate to VMware?

The aim behind migration is to improve the performance, security and day-to-day management of your resources. Some of the reasons most often given for migration include:

  • Change the computing resource upon which the VM runs. One such example is moving a VM from one host to another host or cluster.
  • Load balancing to optimise performance and resource utilisation.
  • Co-locate VMs that communicate with each other so that application performance can be improved.
  • Move VMs to reduce the range of failures.
  • Migrate to new server hardware.

5 steps to take when migrating VMware

Migration planning

It is imperative that the complex nature of migration is fully understood so that you can ensure you have the time, tools, skills and knowledge you need. Looking at the broader picture, you need to take three things into account:

  1. Definition of migration objectives (expected benefits, but also impact on the organisation and users).
  2. Drawing up a detailed schedule.
  3. Assessment of resources required (hardware, software and personnel, provisional budget).

VMware’s documentation provides forms for specifying all the details related to your migration from VMware Aria Operations 8.18 to VMware Aria Operations Saas.
Here’s what you need to specify:

  • The Cloud to which the workload will be migrated: VMware Cloud on AWS, Azure VMware Solution (AVS) or Google Cloud VMware Engine (GCVE).
  • Cluster parameters (instance type, percentage of Slack space, percentage of stable CPU margin).
  • Configuration of virtual computing resources, such as vCPUs, memory and storage.
  • The number of VMs distributed on the workload (optional).
  • Additional vSAN configuration.

Assessing existing environments

A review of the current NSX-V environment should be carried out to identify the following:

  • External and internal networking.
  • Logical networking and security configurations (logical switches, routing, distributed firewall, edge firewall, NAT conversion, VPN and load balancing).
  • Clusters and hosts.
  • VM positioning and relationships.
  • External tools that integrate with vCenter or NSX-V Manager, such as Veeam, VMware Aria Operations Manager, VMware Aria Automation, custom scripts and other tools.

To migrate VMs with disks that are larger than 2 TB, ESXi source and destination hosts need to be running version 6.0 or later.

How to choose your migration strategy and method

Migration strategies define general approaches to migrating workloads.They include elements such as timing, minimising service interruptions and data security. Below, is a summary of some common migration strategies.

  • Hot Migration: moving running VMs from one host to another without interrupting service.
  • Cold migration: VMs are either shut down or suspended before being moved using manual management via the VMware vCenter tool.

Migration methods are the specific techniques used to execute a migration in accordance with the chosen strategy:

  • vMotion is used to move VMs between hosts for load balancing or maintenance purposes.
  • Storage vMotion migrates disk files from a VM to a new datastore without stopping the VM. It is used to optimise storage performance or to migrate to more modern storage systems.
  • VMware HCX offers several migration methods, including Bulk Migration and Replication Assisted vMotion (RAV). It is used for large-scale migration to Cloud environments or data centre consolidation.

Execute migration

Use the vCenter interface to start the migration process. vCenter is not completely essential for all migration operations, but it is highly recommended and does greatly facilitate the process. Other options include direct management via ESXi, VMware vSphere Client or VMware vSphere Replication.

On balance, vCenter greatly simplifies how to manage and execute migrations in a VMware environment and when it comes to complex operations, it is virtually indispensable.

Migration VMware

Validate and optimise post-migration

Check that the VM is running correctly on the target host. Also check that all network and storage configurations are correct and working as expected.

3 ways in which to migrate to VMware

Hot vs. cold migration

Cold migration is the most basic method and requires the VM to be powered down. The advantage is that there is no risk of active memory transfer errors, although the disadvantage is that applications that require high availability are impacted by the shutdown. This strategy is used for major hardware or software upgrades.

Hot migration is a strategy used to overcome the problems of cold migration. It enables a running VM to be moved from one host to another without any interruption to service and makes use of technologies such as vSphere vMotion. The main disadvantage is that it uses very high network bandwidth, which can lead to network saturation if the network is not correctly sized, or if it is being used for other bandwidth-intensive tasks. It is also more complex and costly. One way in which it is used, for example, is for scheduled server maintenance operations without the need to interrupt service.

Using VMware vMotion

vMotion is a module in the VMware vSphere suite that enables hot VM migration without service interruption.

To use vMotion effectively, certain hardware and software requirements must be met:

  1. VMware vSphere Enterprise Plus or vSphere Standard licences with vMotion.
  2. Minimum vSphere version: vSphere 5.1.
  3. Hosts must have compatible processors to ensure seamless VM migration.
  4. VMs must reside on shared storage that can be accessed by both source and target hosts (SAN, iSCSI or NAS).
  5. Each host should have a network interface dedicated to vMotion traffic, ideally on a secure, high-bandwidth network. Enabling Jumbo frames can optimise transfer performance.
vMotion

Migrating with VMware vSphere Replication

VMware vSphere Replication is an extension to VMware vCenter Server and it allows VMs to be replicated and recovered. It provides protection against partial or total site failures and furthermore, is an excellent alternative to storage-based replication. It costs less and allows you to choose the storage provider on both source and target sites.

vSphere Replication can be used with the vCenter Server Appliance or a standard vCenter Server installation and is compatible with version N-1 of vSphere Replication on the paired site.

Recovery point objectives (RPO) are essential when it comes to a replication strategy. The RPO defines the maximum period of data that can be lost in the event of a major failure and helps to shape the replication strategy.

  • A shorter RPO requires more frequent data replication, which increases the load on the network and storage.
  • Stricter RPOs require greater network and storage resources to ensure that data is replicated within the required timeframes.

Depending on business requirements, administrators can set different RPOs for each VM, adjusting the replication frequency accordingly.

All vSphere Replication Action

Free Ebook

How do you respond to rising VMware costs?

Based on our experience of working with a number of companies, we have summarized the changes that have taken place, who is being affected, and what the alternatives might be so that we can provide you with informed strategic advice.

Overcoming challenges

Solving compatibility problems

Virtual machine compatibility

Each version of virtual hardware supports several versions of ESXi. For example, a VM compatible with ESXi 7.0 Update 3 can run on all subsequent versions of ESXi 7.0 Update 3. The following explains how to check VM compatibility.

  1. When creating a VM, select a compatibility that matches the version of the target ESXi host.
  2. If the latest capabilities are not needed, you can choose an earlier version, which helps to facilitate deployment and testing while maintaining compatibility with older hosts.

Host hardware compatibility

vSphere Lifecycle Manager (vLCM) is used to check this compatibility based on the VMware Compatibility Guide (VCG) or the vSAN Hardware Compatibility List (HCL). In order to do this, follow the steps below.

  1. Access vLCM in vSphere Client, select the standalone host or the host in a cluster, then go to the Updates tab and select Hardware Compatibility.
  2. Select the target ESXi host and run a check to generate a detailed compatibility report.
  3. Examine the status of hardware devices (Compatible, Incompatible, Unknown) and manually check specific details if necessary to ensure compatibility.

Managing service interruptions

VMware’s vSphere is a great solution for both lowering instances of unplanned downtime, as well as reducing planned downtime (hardware maintenance, server migrations, etc.) – in general terms, this can account for over 80% of downtime in a data centre.

vSphere High Availability (HA) uses multiple ESXi hosts configured in a cluster to ensure rapid disaster recovery. This feature provides cost-effective high availability for applications running on VMs.

For an even higher level of availability, vSphere Fault Tolerance ensures uninterrupted service continuity, even in the event of hardware failure. vCenter High Availability protects vCenter Server against hardware and software failures, as well as vCenter Server application failures.

Securing data during migration

First of all, you will need to encrypt the data using vSphere vMotion encryption. vSphere vMotion systematically applies encryption when migrating encrypted VMs. If some of your VMs are not encrypted, you can select one of vSphere vMotion’s encrypted options.

The next step is to secure your network with firewalls and intrusion detection and prevention systems. VMware documentation recommends isolating networks:

  • The vSphere management network, because the services running on the management interface enable a hacker to gain access to systems.
  • IP storage traffic, because it is generally unencrypted. It is therefore a good idea to separate it from production traffic.
  • vMotion traffic, since vMotion migration information is transmitted in plain text and is easily visible. To avoid this, check that no Layer 3 router extends this network.

Finally, don’t neglect your VM backups. There are three methods you can follow.

  1. A backup software agent is installed directly on each VM and operates in the same way as it does on a physical server. Data is transferred to the backup infrastructure via the local area network (LAN).
  2. The Backup Agent is installed in the ESX service console and backs up the VMDK files (virtual disks) of each VM.
  3. VMware Consolidated Backup (VCB) centralises VM backup, offloading this task from the ESX server. This reduces backup traffic over the network and frees up server resources to improve VM performance.

Best practices for a successful migration

Detailed planning and documentation

Clear, detailed documentation enables you to plan your migration carefully. To do this, you need to formalise your objectives in order to ensure that the solutions under consideration genuinely meet your company’s needs and will therefore deliver the best possible return on investment. Your objectives should describe the expected results and provide answers to questions such as:

  • Why did you decide to migrate?
  • What impact will migration have on users?
  • What impact will this have on security?
  • What are the risks and how can they be mitigated?
  • What is the estimated cost of migration?
  • What is the estimated return on investment?

Hardware consolidation is not the only aspect of a migration to VMware.

To derive maximum benefit from virtualisation and achieve the best return on investment, a company also needs to consider which people and processes will be involved.

You should document every step of the migration process, including detailed guides to configuration, procedures and problem resolution. In this sense, your runbook will be invaluable.

Perform pre-migration tests

Before migrating your VMware environments, it’s essential to carry out pre-migration tests to identify and resolve potential problems and ensure system compatibility.

Start off by performing automatic checks, such as disk space capacity on the target VM or physical server, and external database accessibility.

Next, you need to check the source environment by verifying:

  • Compatibility of vCenter Server, Platform Services Controller or vCenter Single Sign-On versions with the migration.
  • SSL certificate validity and compatibility.
  • Network connectivity and DNS resolution.
  • Availability of internal and external ports.
  • External database connectivity.
  • Disk space required for exporting configuration data.
  • NTP server validity.
  • Accuracy of all references and identifying information.

The next stage is to then check the target environment in the same way (minimum hardware requirements, administrative privileges, credentials).

Finally, carry out a number of tests:

  • Performance test.
  • Application compatibility testing.
  • Toggle simulation.
  • Safety test.

Communicating with stakeholders

Maintaining open and regular communication with all stakeholders is one of the keys to a successful migration. VMware documentation recommends creating scenarios. Indeed, in organisations with separate management and operational teams, scenario validation helps to understand current and future capacity requirements. With validated scenarios, capacity is reserved to prevent the operational team from increasing resources on workloads, while the management team engages in resource planning for new projects.

VMware migration tools

VMware vCenter Converter

VMware vCenter Converter is an essential tool for migrating physical and virtual machines to VMware environments. It enables P2V (Physical to Virtual) and V2V (Virtual to Virtual) conversions.

In addition to these functions, vCenter Converter enables image conversion between different versions of VMware. Although the tool can also be used to schedule and automate certain tasks, it is primarily designed for specific, manual operations, rather than for large-scale automation management

VMware HCX

VMware HCX is a platform designed to facilitate application migration, workload balancing and business continuity in data centres and Cloud environments. It enables workloads to be moved between on-premises environments and public or private Clouds, while failover and disaster recovery features ensure business continuity. It also provides automation tools for mass migrations and the ongoing management of hybrid environments.

Therefore, VMware vCenter Converter is best suited to complex, large-scale, continuous, hybrid migrations between on-premises and Cloud environments, with a focus on business continuity and advanced automation.

VMware HCX

Other recommended third-party tools

In addition to the tools provided by VMware, we would also recommend several third-party tools based on how efficient they are:

  • Acronis Cyber Protect Cloud offers migration capabilities as well as data backup and protection. It facilitates P2V, V2V, and V2C (Virtual to Cloud) migrations while ensuring data security with features such as integrated anti-malware protection.
  • Carbonite Migrate enables fast, flexible workload migration with minimal downtime. Supports P2V, V2V and V2C migrations, with the option of repeating migration tests until you’re ready to switch to the target environment.
  • Zerto Virtual Replication is designed for disaster recovery, but also offers seamless migration capabilities. It uses continuous replication to ensure application availability during migration between on-premises and Cloud environments.
  • Platespin Migrate offers P2V, V2V and P2P (Physical to Physical) migrations, centralised migration management and pre-configured migrations to minimise downtime.
  • CloudEndure Migration supports migration to leading Cloud providers such as AWS, Azure, and Google Cloud. CloudEndure uses continuous replication to reduce instances of downtime and offer automated migration orchestration.

How Qim info supports your WMware migration

Qim info provides your company with the best possible support in three different areas.

  • Collaboration and transparency: together, we improve team coordination by proposing adapted processes and tools.
    We bring teams together around a common vision to make the best decisions.
  • Custom: no two migrations are alike. Our experts work closely with you to understand your needs and challenges so the best, most appropriate solution for you is implemented.
  • Multi-disciplinary expertise: with almost 20 years of experience, Qim info has developed a wide range of skills in all areas of IT. Whether you choose delegation or project mode with a dedicated team, we have the solution for you.

In conclusion, our Cloud & DevOps Solutions experts will be happy to answer any questions you may have about VMware migration.
If you have any questions about virtualization options other than VMware, such as Proxmox VE, Nutanix or Openstack, against the backdrop of Broadcom’s takeover of VMware, we’re here to help.

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