Virtual Volumes – Page 2

July 17, 2019June 23, 2020

Generating the default VVol Storage Container ID

A VVol datastore, is not a file system, so it is not a traditional datastore. It is just a capacity quota. So when you “mount” a VVol datastore, you aren’t really performing a traditional mounting operation as there is no underlying physical storage to address during the mount. So instead of mounting some storage device, you are mounting what is called a storage container. This is the meta data object that represents the certain amount of capacity that can be provisioned from a given array. An array can have more than one storage containers, for reasons of multi-tenancy or whatever.

In a VMFS world, when you go to create a new datastore, you pass it the serial number of the storage you want to format with VMFS. You know that serial, because, well, you created the storage device. When you “mount” a VVol datastore, instead of a device serial, you supply the storage container UUID. It comes in the form of vvol:e0ad83893ead3681-b1b7f56a45ff64f1. Of course the characters will vary a bit.

July 16, 2019July 17, 2019

Mounting a VVol Datastore with PowerCLI

I’ve been making a lot of updates to my PowerShell module around VVols recently and this was the last “table stakes” cmdlet I wanted to add. There are certainly more to come, but now we definitely have the basics. In 1.2.2.1 release of the PowerShell module I added a cmdlet called Mount-PfaVvolDatastore.

As of today we support a single VVol datastore–though we are working on adding support for more than one.

July 8, 2019July 8, 2019

Registering VASA with PowerShell

Registering VASA providers is the first step in setting up VVols for a given vCenter, so automating this process is something that might be of interest to folks. We currently have this process in our vSphere Plugin, as well as in our vRO plugin, and of course you can do it manually. What about PowerShell? Well we have that too!

In our PowerShell Pure/VMware module there are three new cmdlets:

new-pfavasaprovider
get-pfavasaprovider
remove-pfavasaprovider

June 11, 2019June 11, 2019

First Class Disks and VVols

One of the major advantages we have seen with VVols is making a virtual disk a first class citizen on the array. We can restore, copy, replicate them (and their VMs) as storage objects were meant to be restored, copied, replicated etc.

Though one thing about virtual disks is that by default–they are not first class citizens in vSphere, VVols or otherwise. To create one, it has to be associated with a VM.

To retrieve one in PowerCLI (for example) get-harddisk requires a datastore or a VM to return a result:

Same if I want to create a new one:

February 13, 2019February 13, 2019

PowerCLI and VVols Part VIII: Running a Failover–Planned Migration

In the previous post in this series I explored how to run a VVol-based test failover of a virtual machine. Now I will walk through running an actual failover.

There are two types of failovers; a planned migration (everything is up an running) and a disaster recovery failover (part or all of the original site is down).

For this post, I will start with running a planned migration.

February 11, 2019February 13, 2019

PowerCLI and VVols Part VII: Synchronizing a Replication Group

In this post, I will overview how to synchronize a VVol-based replication group with PowerCLI. See previous posts below for more context:

This post is somewhat specific to Pure Storage–the cmdlets of course are universal, but behaviors may not correlate to your storage array. So if you are using VVols on a non-Pure array, certainly consult your vendor.

Furthermore, this is certainly specific to PowerCLI when it comes to the commands. With that being said, the fundamentals on how this works with Pure is common for all orchestration tools, so you should be able to use this information for other tools. Though of course the cmds/syntax will be different.

December 10, 2018June 26, 2019

Updating a volume group name on the FlashArray for VVols

The FlashArray implementation of Virtual Volumes surfaces VMs on the FlashArray as standard volume groups. The volume group being named by the virtual machine name. Each VVol is then added and removed to the volume group as they are provisioned or deleted. These objects though are fairly flexible–we do not use the volume group as a unique identifier of the virtual machine–internally we use key/value tags for that.

The benefit of that design is that you can delete the volume groups, rename them, or add and remove other volumes to it. Giving you some flexibility to group related VMs or whatever your use case might be to move things around, without breaking our VVol implementation.

December 7, 2018March 5, 2019

PowerCLI and VVols Part VI: Running a Test Failover

This post I will talk about using PowerCLI to run a test failover for VVol-based virtual machines. One of the many nice things about VVols is that in the VASA 3.0 API this process is largely automated for you. The SRM-like workflow of a test failover is included–so the amount of storage-related PowerShell you have to manually write is fairly minimal.

July 30, 2018

Virtual Volumes and Array Snapshots Part I: Managed Snapshots

One of the first technical benefits users can enjoy around VVols is the use of snapshotting. Snapshots created through VMware of VMs have always been a point of contention which as severely limited their usability (see a post I did around the performance impact of them here).

With VVols, when you right-click on a VM and choose take snapshot, VMware does not create the performance-impacting delta VMDK files that were traditionally used, but instead VMware entirely offloads this process to the array. So the array creates the snapshots and VMware just tracks them.

But since VMs are now a collection of individual volumes on the array (a VVol is just an array volume) you can also snapshot and restore individual virtual disks as well directly on the array.

So what does all of this mean?

Continue reading “Virtual Volumes and Array Snapshots Part I: Managed Snapshots”

July 9, 2018March 4, 2020

Troubleshooting Virtual Volume Setup

VVols have been gaining quite a bit of traction of late, which has been great to see. I truly believe it solves a lot of problems that were traditionally faced in VMware environments and infrastructures in general. With that being said, as things get adopted at scale, a few people inevitably run into some problems setting it up.

The main issues have revolved around the fact that VVols are presented and configured in a different way then VMFS, so when someone runs into an issue, they often do not know exactly where to start.

The issues usually come down to one of the following places:

Initial Configuration
Registering VASA
Mounting a VVol datastore
Creating a VM on the VVol datastore