Vmotion without shared storage

I have been running into issues on my home lab when it comes to load balancing. Apparently with the release of the VSphere 5.1 there is a new feature that allows you to migrate running images between hosts without shutting them down first.

The requirements are as follows

Requirements and Limitations for vMotion Without Shared Storage

A virtual machine and its host must meet resource and configuration requirements for the virtual machine files and disks to be migrated with vMotion in the absence of shared storage.

vMotion in an environment without shared storage is subject to the following requirements and limitations:

The hosts must be licensed for vMotion.

The hosts must be running ESXi 5.1 or later.

The hosts must meet the networking requirement for vMotion. See vSphere vMotion Networking Requirements.

The virtual machines must be properly configured for vMotion. See Virtual Machine Conditions and Limitations for vMotion in the vSphere Web Client

Virtual machine disks must be in persistent mode or be raw device mappings (RDMs). See Storage vMotion Requirements and Limitations.

The destination host must have access to the destination storage.

When you move a virtual machine with RDMs and do not convert those RDMs to VMDKs, the destination host must have access to the RDM LUNs.

Consider the limits for simultaneous migrations when you perform a vMotion migration without shared storage. This type of vMotion counts against the limits for both vMotion and Storage vMotion, so it consumes both a network resource and 16 datastore resources. See Limits on Simultaneous Migrations in the vSphere Web Client.

 

Migration with vMotion in Environments Without Shared Storage

You can use vMotion to migrate virtual machines to a different host and datastore simultaneously. In addition, unlike Storage vMotion, which requires a single host to have access to both the source and destination datastore, you can migrate virtual machines across storage accessibility boundaries.

In vSphere 5.1 and later, vMotion does not require environments with shared storage. This is useful for performing cross-cluster migrations, when the target cluster machines might not have access to the source cluster’s storage. Processes that are working on the virtual machine continue to run during the migration with vMotion.

You can place the virtual machine and all of its disks in a single location or select separate locations for the virtual machine configuration file and each virtual disk. In addition, you can change virtual disks from thick-provisioned to thin-provisioned or from thin-provisioned to thick-provisioned. For virtual compatibility mode RDMs, you can migrate the mapping file or convert from RDM to VMDK.

vMotion without shared storage is useful for virtual infrastructure administration tasks similar to vMotion with shared storage or Storage vMotion tasks.

Host maintenance. You can move virtual machines off of a host to allow maintenance of the host.

Storage maintenance and reconfiguration. You can move virtual machines off of a storage device to allow maintenance or reconfiguration of the storage device without virtual machine downtime.

Storage load redistribution. You can manually redistribute virtual machines or virtual disks to different storage volumes to balance capacity or improve performance.

 

 

Migrate a Virtual Machine to a New Host and Datastore by Using vMotion in the vSphere Web Client

You can move a virtual machine to another host and move its disks or virtual machine folder to another datastore. With vMotion, you can migrate a virtual machine and its disks and files while the virtual machine is powered on.

You can perform vMotion in environments without shared storage. Virtual machine disks or contents of the virtual machine folder are transferred over the vMotion network to reach the destination host and datastores.

To make disk format changes and preserve them, you must select a different datastore for the virtual machine files and disks. You cannot preserve disk format changes if you select the same datastore on which the virtual machine currently resides.

Prerequisites

Verify that your hosts and virtual machines meet the necessary requirements. See Requirements and Limitations for vMotion Without Shared Storage.

Required privilege: Resource.HotMigrate

Procedure

1

Right-click the virtual machine and select Migrate.

a

To locate a virtual machine, select a datacenter, folder, cluster, resource pool, host, or vApp.

b

Click the Related Objects tab and click Virtual Machines.

2

Select Change both host and datastore and click Next.

3

Select the destination resource for the virtual machine migration.

4

Select a destination host or cluster for the virtual machine, and click Next.

Any compatibility problems appear in the Compatibility panel. Fix the problem, or select another host or cluster.

Possible targets include hosts and fully automated DRS clusters. You can select a non-automated cluster as a target. You are prompted to select a host within the non-automated cluster.

5

Select the format for the virtual machine’s disks.

Option

Action

Same format as source

Use the same format as the source virtual machine.

Thick Provision Lazy Zeroed

Create a virtual disk in a default thick format. Space required for the virtual disk is allocated during creation. Any data remaining on the physical device is not erased during creation, but is zeroed out on demand at a later time on first write from the virtual machine.

Thick Provision Eager Zeroed

Create a thick disk that supports clustering features such as Fault Tolerance. Space required for the virtual disk is allocated at creation time. In contrast to the thick provision lazy zeroed format, the data remaining on the physical device is zeroed out during creation. It might take longer to create disks in this format than to create other types of disks.

Thin Provision

Use the thin provisioned format. At first, a thin provisioned disk uses only as much datastore space as the disk initially needs. If the thin disk needs more space later, it can grow to the maximum capacity allocated to it.

6

Assign a storage profile from the VM Storage Profile drop-down menu.

Storage profiles define the storage capabilities that are required by the applications running on the virtual machine.

7

Select the datastore location where you want to store the virtual machine files.

Option

Action

Store all virtual machine files in the same location on a datastore.

Select a datastore and click Next.

Store all virtual machine files in the same Storage DRS cluster.

a

Select a Storage DRS cluster.

b

(Optional) To not use Storage DRS with this virtual machine, select Disable Storage DRS for this virtual machine and select a datastore within the Storage DRS cluster.

c

Click Next.

Store virtual machine configuration files and disks in separate locations.

a

Click Advanced.

b

For the virtual machine configuration file and for each virtual disk, select Browse, and select a datastore or Storage DRS cluster.

c

(Optional) If you selected a Storage DRS cluster and do not want to use Storage DRS with this virtual machine, select Disable Storage DRS for this virtual machine and select a datastore within the Storage DRS cluster.

d

Click Next.

8

Select the migration priority level and click Next.

Option

Description

Reserve CPU for optimal VMotion performance

vCenter Server attempts to reserve resources on both the source and destination hosts to be shared among all concurrent migrations with vMotion. vCenter Server grants a larger share of host CPU resources. if sufficient CPU resources are not immediately available, vMotion is not initiated.

Perform with available CPU resources

vCenter Server reserves resources on both the source and destination hosts to be shared among all concurrent migration with vMotion. vCenter Server grants a smaller share of host CPU resources. If there is a lack of CPU resources, the duration of vMotion can be extended.

9

Review the information on the Review Selections page and click Finish.

vCenter Server moves the virtual machine to the new host and storage location. Event messages appear in the Events tab. The data that appears in the Summary tab shows the status and state throughout the migration. If errors occur during migration, the virtual machines revert to their original states and locations.

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