Planet vSphere-land

The availability of vMotion and svMotion, provided you have a license that allows it, in vSphere are some of its key features. The DRS and SDRS functionality will use vMotion and svMotion to better use the available resources. And you as a vSphere administrator can use it to facilitate your work. Just think of how easy patching or datastorecluster maintenance becomes with the help of these two f...

One of the hot new features in vSphere 5 was the introduction of SDRS. And with SDRS came the concept of affinity rules for VMs and VMDKs. Cormac, aka @VMwareStorage, posted a nice overview of the SDRS affinity rules in Storage DRS Affinity & Anti-Affinity Rules. Since then several posts have appeared on the subject of SDRS affinity rules.  To list just a few: Frank Denneman: Impact of In...

I often hear people making comments around Storage IO Control and Storage DRS IO Load Balancing being one and the same thing. It has been one of those myths that has been floating around for a long time now, and with this article I am going to try to stop it. I guess where this myth comes from is that when you create a Datastore Cluster and you enable Storage DRS IO Load Balancing then it config...

As part of the Technical Marketing team of VMware focusing on the vSphere platform I contribute to the vSphere blog on VMware.com. From this point forward I will post a link to new articles posted on the vSphere blog. SDRS maintenance mode impossible because “The virtual machine is pinned to a host.” Blog post on blogs.vmware.com/vsphere/ is a post from: frankdenneman.nl

Storage DRS load balancing frequency differs from DRS load balance frequency, where DRS runs every 5 minutes to balance CPU and memory resources, Storage DRS uses a far more complex load balancing scheme. Let’s take a closer look at Storage DRS load balancing. Default invocation period The invocation period of Storage DRS is every 8 hours and uses what’s called past-day statistics. Storage D...

Combining datastores located on different storage arrays into a single datastore cluster is a supported configuration, such a configuration could be used during a storage array data migration project where virtual machines must move from one array to another array, using datastore maintenance mode can help speed up and automate this project. Recently I published an article about this method on t...

Recently I received the question if you can connect multiple compute (HA and DRS) clusters to a single Storage DRS datastore cluster and specifically how this setup might impact Storage IO Control functionality. Let’s cover sharing a datastore cluster by multiple compute clusters first before diving into details of the SIOC mechanism. Sharing datastore clusters Sharing datastore clusters acros...

Lately I have been playing around with the new Storage related features in vSphere 5. One of the novelties is that you can now unmount a VMFS datastore and detach a SCSI LUN through the API. To be able to unmount a datastore, some conditions have to be met. In the vSphere Client you get an informative popup that tells what is prohibiting the datastore unmount. If not all conditions are met, you ...

Last year I wrote an article called Automating Storage DRS & Datastore Cluster Management in vSphere 5 and I provided a pretty comprehensive vSphere SDK for Perl script to help administrators automate Storage DRS configurations. These past few months I have noticed an increase in interest on the VMTN developer forums relating to Storage DRS. Majority of the questions has been related to whic...

By default Storage DRS applies an Intra-VM affinity rule to all new virtual machines in the datastore cluster. The Intra-VM affinity rule keeps the virtual machine files, such as VMX file, log files, vSwap and VMDK files together on one datastore. Keeping all files together on one datastore allows ease of troubleshooting. However Storage DRS load balance algorithms may benefit from distributin...

I was meeting with a customer today and had to stop for a second when they said they were using 10 TB datastores in vSphere 4.1. At first I was going through my head of maybe NFS? No they are an all block shop. Oh wait yeah, extents. They were using 2 TB -512 byte luns to create a giant Datastore. I asked, why? The answer was simple, “so we only manage one datastore.” I responded wit...

In its basic form Storage DRS can be used together with any array, however there are a few combinations of Storage array features and Storage DRS features that don’t mix easily. One of the most sought after question is can Storage DRS work with Array based Auto-tiering? And the answer is yes, yes you can use initial placement and out of space avoidance features that Storage DRS offers, however...

On my blog article for yesterday “Rob M” commented that the default affinity rule for Storage DRS (SDRS), keep VM files together, did not make sense to him. One of the reasons this affinity rule is set is because customers indicated that from an operational perspective it would be easier if all files of a given VM (vmx / vmdk’s) would reside in the same folder. Especially troub...

Lately I have received many questions about the interoperability between HA and affinity rules of DRS and SDRS. I’ve created a table listing the (anti-) affinity rules available in a vSphere 5.0 environment. Technology Type Affinity Anti-Affinity Respected by VMware HA DRS VM-VM Keep virtual machines together Separate virtual machines No VM-Host Should run on hosts in group Should not ru...

I was just playing around in my lab and created a whole bunch of VMs when I needed to deploy to large virtual machines. Both of them had 500GB disks. The first one deployed without a hassle, but the second one was impossible to deploy, well not impossible for Storage DRS. Just imagine you had to figure this out yourself! Frank wrote a great article about the logic behind this and there is no rea...

Recently an interesting question was raised about what happens if enough free space is available in the datastore cluster but not enough space is available per datastore during placement of a virtual machine. This scenario is often referred as a defragmented datastore cluster. The short answer is that if not enough space available on any given datastore, then Storage DRS starts to consider mig...

Somebody asked me if VMFS3 multi-extents datastores are supported in a datastore cluster. Although they are supported and fully operational in Storage DRS, one must ask if this construct of large datastores should be used in a datastore cluster. Resource aggregation and flexibility Storage DRS Datastore clusters offer flexibility in adding and removing datastores dynamically and allow the admini...

This article is a part of the series on architecture and design on datastore clusters. This article zooms in on why it’s recommended to use similar type disks in a datastore cluster. In-tier balancing solution SDRS can be considered as an “in-tier” balancing solution, suggesting that a datastore cluster should be populated with datastores that provide similar performance, continuity, capac...

During our presentation at the Dutch VMUG Event 2011, Alan and myself showed how several entries of the Top 10 vSphere 5 Features session could be automated with the help of PowerCLI. In the session we showed several demos. This post is the first in a series, that will publish and document most of the scripts we used for the demos. On the first position in the Top 10 we have Storage DRS. This fe...

The first article in the series about architecture and design decisions series focuses on the connectivity of the datastores within the datastore cluster. Connectivity between ESXi hosts and datastores in the datastore cluster affects initial placement and load balancing decisions made by DRS and SDRS. Although connecting a datastore to all ESXi hosts inside a cluster is a common practice, we st...

Storage DRS extends the DRS feature set to the storage space. The primary element used by SDRS is a datastore cluster. Introducing the concept of datastore clusters can affect or shift the paradigm of storage management in virtual infrastructures. This article is the start of a short series of articles focusing on the design considerations of datastore clusters Datastore cluster concept Let’s...

During VMworld I noticed a lot of focus of the attendees was on the IO load balancing features of Storage DRS (SDRS), however SDRS is more than only IO load balancing. Both space load balancing feature and initial placement are just as incredible, powerful and as useful as IO load balancing. Actually the term space load balancing isn’t really doing the algorithm any justice as it sounds it m...

During VMworld I received multiple questions around support for vSphere Storage DRS with vSphere Site Recovery Manager (SRM), we even had this question during our session and my answer was “Yes it does”. During some of the other sessions presenters stated that it was unsupported. Scott Lowe also mentions recalling the fact that it was mentioned somewhere down the line to be unsupport...

A couple of weeks ago I wrote an article about Storage DRS (hereafter SDRS) interoperability and I mentioned that using SDRS with Auto-Tiering solutions should work… Now the truth is slightly different, however as I noticed some people  started throwing huge exclamation marks around SDRS I wanted to make a statement. Many have discussed this and made comments around why SDRS would not be ...

Storage DRS is probably one of, if not the coolest feature in vSphere 5. Storage DRS allows you to cluster your datastores into what is known as a datastore cluster (storage pod) and automatically balances both your storage I/O and capacity just like DRS does with your compute. The user interface is extremely easy to use but as always, if you need to click through several screens to get to the o...