Datastores fields explanation

 

How to check ESXi has consistent path across the SP

When you use vMotion or DRS with an active-passive SAN storage device,
make sure that all ESXi systems have consistent paths to all storage processors.
Not doing so can cause path thrashing when a vMotion migration occurs.

 

Storage DRS FAQ

Storage DRS Cluster

 

What are functions get enabled when you enable storage DRS?

Space load balancing among datastores within datastore cluster

I/O load balancing among datastores within datastore cluster

Initial placement for virtual disks on space and I/O workload

When you disable storage DRS all the above functions gets disabled but you can specifically disabled I/O load balancing. When you disable Storage DRS unlike DRS all settings are preserved to the point where Storage DRS was disabled.

When an initial placement does happen?

1. When VM is created
2. When VM is cloned
3. When VM is migrated to another datastore cluster
4. When you add a disk to existing VM

On what basis Initial recommendations are made?

1. Datastores user defined space utilization threshold
2. I/O latency
3. Anti-affinity rules

When is storage DRS invoked?

1. It is invoked at the configured frequency i.e. every 8 hours (this is default)
2. When space of one of the datastore in a datastore cluster exceeds user configurable space utilization threshold.

What happens when storage DRS is invoked?

When storage DRS is invoked it checks each datastores space utilization and I/O latency values against threshold. For I/O latency, storage DRS uses the 90^th percentile I/O latency measured over the course of a day to compare against the threshold.

What are the reasons for recommendations?

1. Balance datastore space use
2. Balance datastore I/O load

When does storage DRS makes mandatory recommendations

The datastore is out of space

Anti-affinity or affinity rules are being violated

The datastore is entering maintenance mode and must be evacuated

However optional recommendations are made when datastore is about to run out of space or when adjustment should be made for space and I/O load balancing.

Does virtual machine states are considered when Storage DRS is invoked?

Storage DRS is focused on disk space. Therefore state of virtual machine does not matter. So Storage DRS considers moving virtual machine which are powered on or powered off for space balancing.

How many automation level are available for Storage DRS?

In storage DRS unlike DRS only two automation level are available.

No Automation (Manual): Same as DRS i.e. both initial placement and migration recommendation needs to be implemented manually.

Fully automated: Everything is automated without any manual intervention

What are requirements of datastore cluster?

• Datastore cluster must contain similar datastore. It can have different sizes, disks and even different arrays and vendors. But following types of datastore cannot exist
  • NFS & VMFS cannot be mixed, you can make VMFS based datastore cluster or NFS based datastore cluster
  • Replicated datastores cannot be mixed with non-replicated datastores.
• All hosts must be ESXi5.0 or above
• Datastores shared across multiple datacenters cannot be included in datastore cluster
• VMware recommends not mixing array which has hardware acceleration support with non-hardware acceleration support. Datastores in a datastore cluster must be homogenous to take advantage of hardware assisted features

Check Storage Compliance with Virtual Machine Storage Profile

Procedure
1 In the vSphere Client, select View > Management > VM Storage Profiles.
2 Select a virtual machine storage profile from the inventory.

3. Select the Virtual Machines tab.
    The Virtual Machines tab lists the virtual machines and the virtual disks that use the selected virtual machine storage profile.

4 Click Check Compliance Now.

The Compliance Status column shows whether the virtual machine files or the virtual disks use datastores that are compliant or noncompliant with the selected virtual machine storage profile.

Associate a Virtual Machine Storage Profile with a Virtual Machine and Its Virtual Disks

You can associate a virtual machine storage profile with a virtual machine to define the storage capabilities that are required by the applications running on the virtual machine.
You can associate a virtual machine storage profile with a powered-off and powered-on virtual machine.

Below is conceptual diagram. Here we

1. First defined/read storage capabilities (i.e. system/User defined)
2. Create Storage profiles
3. Then these storage profiles are applied to VM

Procedure

1. Open the Profiles tab of a virtual machine.

Right-click a virtual machine from the inventory and select VM Storage Profile > Manage Profiles

2. Associate the virtual machine home files with a virtual machine storage profile from the Home VM Storage Profile drop-down menu.

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NOTE The virtual machine home files include the file types .vmx, .vmsd, .nvram, and so on.

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3 (Optional) Click Propagate to disks to associate all virtual disks with the same virtual machine storage profile.
4 Under VM storage profiles for virtual disks, associate each virtual disk with a different virtual machine storage profile from the VM Storage Profile drop-down menu.
5 Click OK.

The virtual machine storage profile name appears in the VM Storage Profiles pane of the Summary tab for the virtual machine

Create a Virtual Machine Storage Profile

Procedure

1. In the VM Storage Profiles view of the vSphere Client, click Create VM Storage Profile.

The Create New VM Storage Profile wizard appears.

2. On the Profile Properties page, type a name and a description for the virtual machine storage profile, and
click Next.

3. On the Select Storage Capabilities page, define storage requirements for the virtual machine storage profile
by selecting one or more storage capabilities from the list, and click Next.

A datastore that has any of the selected capabilities will be compliant with the virtual machine storage profile.

4. On the Ready to Complete page, verify the virtual machine storage profile settings, and click Finish.

 

The new virtual machine storage profile appears one level under the VM Storage Profiles folder in the inventory.

Enable Virtual Machine Storage Profiles on a Host or a Cluster

Before you can use virtual machine storage profiles, you must enable them on a host or a cluster.

Prerequisites

Verify that the host or all the hosts in the cluster for which you want to enable virtual machine storage profiles
are licensed with a vSphere Enterprise Plus license key.

Procedure

1. In the VM Storage Profiles view of the vSphere Client, click Enable VM Storage Profiles.The Enable VM Storage Profiles window appears. The window shows all available clusters and hosts, their licensing status, and whether virtual machine storage profiles are enabled or disabled for the host or the cluster.

2. To enable virtual machine storage profiles, select a host or a cluster whose status is Disabled or Unknown and click Enable. The status of the host or cluster changes to Enabled in the VM Storage Profile Status column.

How to Assign User-Defined Storage Capability

Procedure
1 In the vSphere Client, select View > Inventory > Datastores and Datastore Clusters.
2 Right-click a datastore from the inventory and select Assign User-Defined Storage Capability.
3 Select a storage capability from the list of storage capabilities and click OK.

In the below screen you will Storage Capability Window being updated (high lighted) with Replicated Store as this was the user defined capability we selected in above.

View Existing Storage Capabilities

Procedure
1. In the vSphere Client, select View > Management > VM Storage Profiles.

2. In the VM Storage Profiles view of the vSphere Client, click Manage Storage Capabilities.
The Manage Storage Capabilities dialog box appears.

3. View the names and descriptions of the storage capabilities in the Name and Description column.

4. View the System and User-defined types of the existing storage capabilities.
       a Click the Type column to sort the storage capabilities by type.
       b View the storage capabilities whose type is System.
       c View the storage capabilities whose type is User-defined.

Storage Views–Various way to interpret relationships

Information about physical storage elements appears on the Storage Views tab. It includes such data as storage arrays, array IDs, and so on. This type of information can be helpful when you need to track virtual machine-to-storage relationships and configuration, or to identify any changes in physical storage configuration. You can simply establish this relation by selecting appropriate menu from drop down as shown below

Below is the view while selecting “Show all Virtual Machines”

 

You can see above as the view changes, the options column changes to provide you more relevant information