VMware vMotion is the core live migration capability used to move running workloads with minimal disruption. If it is not planned correctly, routine maintenance windows can quickly turn into avoidable production incidents.

Short answer: vMotion transfers a VM runtime state (memory, registers, network identity) to a compatible target host so services can continue with minimal interruption.

Quick Summary

Broadcom TechDocs states that with vMotion, VM processes continue running during migration.
Main migration types are Cold Migration, Hot Migration (vMotion), and Storage vMotion.
The migration wizard runs compatibility checks against destination host/cluster criteria before execution.
CPU compatibility baseline: source and destination CPUs must be in the same vendor class (AMD or Intel).
EVC improves interoperability by masking CPU features to a shared baseline mode.
Encrypted vMotion secures confidentiality, integrity, and authenticity of migration traffic; for unencrypted VMs, Opportunistic is default and Required enforces encryption.
In the vCenter simultaneous migration table (vSphere 6.0-8.0 row), derived host limits are vMotion: 8, Storage vMotion: 2, vMotion Without Shared Storage: 2.

What Is VMware vMotion

vMotion is a live migration feature that moves a powered-on VM between ESXi hosts. The goal is not only relocation, but continuity.

Typical use cases:

Draining hosts before planned maintenance
Rebalancing cluster capacity
Moving workloads away from degraded hosts

How vMotion Works

At a high level:

Compatibility validation: destination host/cluster checks are executed by the migration wizard.
State transfer: VM runtime data is copied to the target.
Cutover: execution continues on the destination host with a short transition window.

This approach makes maintenance windows safer in production environments.

Migration Types and Correct Usage

Cold Migration

Moves powered-off or suspended VMs across hosts/datastores.

Hot Migration (vMotion)

Moves powered-on VMs across compute resources with minimal disruption.

Storage vMotion

Moves VM disks to another datastore while the VM keeps running.

vMotion Prerequisites

Most migration failures come from missing prerequisites:

CPU compatibility: source and destination hosts must be in the same vendor class.
EVC baseline: required for many heterogeneous clusters.
vMotion network readiness: source/target hosts must be configured correctly.
Wizard compatibility results: warnings and errors must be interpreted correctly before execution.

Traffic Isolation with vMotion TCP/IP Stack

TechDocs explicitly separates migration traffic models:

vMotion TCP/IP stack: isolates live migration traffic.
Provisioning TCP/IP stack: isolates cold migration, clone, and snapshot traffic.

This improves operational control over routing, gateway, and DNS behavior for migration paths.

When to Use Encrypted vMotion

Encrypted vMotion protects migration traffic confidentiality, integrity, and authenticity.

For unencrypted VMs:

Opportunistic (default): encrypt if both hosts support encrypted vMotion.
Required: allow only encrypted migration; fail if unsupported.

Required is generally safer in regulated or multi-tenant environments.

Simultaneous Migration Limits

Use vCenter limits directly for planning migration windows.

Example (vSphere 6.0-8.0 row):

Operation	Derived Limit Per Host	Host Resource Cost
vMotion	8	1
Storage vMotion	2	4
vMotion Without Shared Storage	2	4

These values are important when scheduling parallel maintenance operations.

Practical Operations Note

In multi-site environments, including enterprise teams around Ankara, vMotion should be treated as a repeatable operating standard rather than a one-off action.

Recommended baseline runbook:

Daily: host health and alarm review
Weekly: EVC and compatibility risk sweep
Monthly: migration capacity drill for maintenance scenarios

Frequently Asked Questions

What is the difference between vMotion and Storage vMotion?

vMotion moves compute runtime; Storage vMotion moves disk location while running. They can be combined when needed.

Is shared storage always required?

Traditional patterns rely on it, but TechDocs also covers supported scenarios without shared storage.

Can I vMotion from Intel to AMD hosts?

Not in standard compatibility flow. The official guidance requires same vendor class.

What is the most critical pre-check?

Migration wizard compatibility output. Ignoring blocking errors introduces avoidable production risk.

Conclusion

When designed correctly, vMotion turns maintenance from outage-focused work into continuity-focused operations. Compatibility checks, EVC strategy, traffic isolation, and migration concurrency limits should be handled as one operating model.

For environment-specific vMotion planning, you can contact our team.

Sources

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What Is VMware vMotion and How Does It Work? (2026 Guide)