Tuesday, October 6, 2015

vSphere 5.5 Update 3 Patch Available

The Best Intentions

It was obvious and natural; the Right Thing to do.  In preparation for a deployment across all vSphere hosts we took the step of insuring the latest updates. And since we are running vSphere 5.5, this meant Update 3.

There was even some chest-thumping among our small team of generalists as they completed the task within short order.  And why not?

That was Short-Lived

Within 2 weeks we were crestfallen. Update 3 introduced a service-impacting defect involving seldom-used (sic) snapshots.  KB 2133118 was released to announce "unexpected signal: 11."  Consolidate or delete a snapshot and you may suffer a VM outage.

To be honest, I find the KB lacking in details--there are no specifics to indicate contributing factors or degree of impact across customers.

A New Hope?

While we haven't been impacted (whew!), I'm happy to see that today brings the release of patch ESXi550-201510401-BG to address this issue.

Fire up Update Manager and start patching!  Let us know how it goes, because I'm not sure that we wish to be first on this one.


Thursday, September 24, 2015

Snazzy-Up Your PowerShell with a GUI

I’d like to say that I work with virtualization every day, and in a way I do.  Virtually every server in my employer’s environment is virtualized (see what I did there?).

That we are a small team in an SME environment dictates that we are I.T. generalists.  That’s not a curse—that’s variety and opportunity alleviating the mundane.  It’s also an opportunity to automate the mundane. 

For the purposes of user provisioning I wanted to use PowerShell for identity management on a shoestring budget.   As with many things, creating is harder than destroying; this provisioning needs a GUI.  Pick an OU, pick a user/template, and copy with new details.  While that’s how I got to the point of driving a GUI with PowerShell, it’s difficult to effectively convey a company-specific workflow.  So I’ll demonstrate with something virtualization-focused.

With a little bit of Googling I found an older option or two along with .NET-based Windows Presentation Foundation (WPF).  .NET this plus .NET that sounded appealing with me, so I dug in further. 

There are solid posts to be found that give you all that you need.  I’m working against some of my musings, so here I share my journey toward the same end result.

At a higher level the process is relatively simple:
  • Generate a GUI form in Extensible Application Markup Language (XAML).
  • Load the XAML in PowerShell with some minor (automated) transformations.
  • Instantiate the WPF form.
  • Create variables for working with our GUI elements.
  • Define PowerShell event handlers for each GUI element, incorporating our workflow within.

Generating Your GUI’s XAML

To generate the GUI we need something that will generate XAML that WPF can handle.  Anything from Visual Studio 2010 on up will do here.  I used Visual Studio 2015 Community since it is full featured with an investment of $0.

Open Visual Studio and create a new project.  Choose WPF Application under Visual C# Templates and give it a name.  Any name will do—we only want the XAML which this project will generate.

2015-09-23 20_26_39-Start Page - Microsoft Visual Studio

What you will notice is a blank window in the main center pane, labeled MainWindow.xaml.  The pane below contains the XAML in which we are interested. 

LetUsWPF - Main Window

I find it best to turn on the toolbox from the View menu and pin it to the side bar this yields an environment tailored for creating window forms.

Let’s use the toolbox to drag and position a few controls:
  • A ComboBox selector for Cluster
  • A DataGrid to display VMs within a selected Cluster.
  • A Button for launching a selected VM’s console.
  • A Label or three for clarity.
While we can add these controls in any order, Visual Studio will set the form’s tab order based on the order of definition.  That’s not a particularly big deal because of a neat Visual Studio feature:  the GUI form is tied to the XAML and the XAML is tied to the GUI form. We can adjust the tab order by re-ordering the text inside the XAML pane copy and paste!

With each control use the properties pane and give it a unique name, which we will  use later to bind to PowerShell variables.  I like to start all label control names with “label_” for easier exclusion from this binding process.

LetUsWPF - Drawn Form

Loading the XAML

All we need from Visual Studio is the XAML, which we will copy and paste into a PowerShell here-string.  The string isn’t perfect for PowerShell processing yet, so we’ll also rework it to take care of these issues and cast as XML:

Instantiating the GUI Form

Next we need to load the PresentationFramework assembly and process our form so that it can be presented:

Creating GUI Variables

We need to be able to work with the controls on form that comprise our GUI, and that means variables that let us get/set values and work with other properties and methods afforded to us by WPF.   

We can do this rather handily in PowerShell by invoking Set-Variable for nodes within the XML that comprises our form.  The iteration of those nodes will return Label controls as well, which we’ll ignore based on giving them a prefix of “Label_”, which was mentioned earlier:

Defining Event Handlers

WPF will send asynchronous signals (events) to our script when the GUI is acted upon.  Examples include when a selection is made, a button is clicked, and when the window is instantiated or destroyed. 

Defining event handler functions in our PowerShell lets us dictate our workflow:
  • When the window is created, connect to vCenter, get a list of clusters, and populate the cluster ComboBox.
  • When a selection is made in the cluster ComboBox, get a list of cluster VMs and populate the details DataGrid.
  • When a VM selection is made in the DataGrid, enable the console Button.
  • When the console Button is clicked, launch a vSphere Remote Console window.
  • When the window is closed, disconnect from vCenter
Anything is possible, of course.  Here’s our event handlers:

Final Bits

There’s not much left!  Define the vCenter server against which we will operate and display the form:


Run this little puppy and off we go.  Pick a cluster from the drop-down to see a list of VMs and click the column headers to if you don’t like it ordered by VM name.  Choose a VM and the console button becomes active so long as the VM state is “PoweredOn.”

LetUsWPF - Pick Cluster

LetUsWPF - Pick VM

What else?

  • My error checking and validations are non-existent--Add some.
  • Add another button to perform another task.
  • Change what VM properties appear in the DataGrid.
  • Do something else and have fun with it!

Full Code

You can grab the full code from here.

Proper Attribution is Proper

Thursday, September 17, 2015

Musings of an Infrequent Blogger

Writing is hard.
That's not the case for everyone, of course, but it holds true for me.  If you know me on a personal or professional level you've heard me say this before.  The odd thing is, I enjoy writing.  And because of that I tend to focus on this topic.

I have reasons not to write.

It's a silly idea/topic/thought

This is a powerful one for me and stops me the most often. It's also the quickest way out.  I question myself by nature, so there's no surprise here.  I'm still not certain that I'll hit publish on this post!

Suck it up and write anyway.

It's never quite right

One of the things that I enjoy most in the writings of others is the multitude of ways to say the same thing. The simplicity of some, the eloquence of others.  Let's not even talk about grammar, misspellings, etc.  Whether I'm writing here or within the corporate walls, I can tell you that I've reworked virtually every paragraph multiple times.

Practice makes perfect?  No, but it certainly improves.

Others have already written about this

Why bother covering a topic that so many others already have?  Fear of getting lost among similar technical articles and not managing to stand out.

Not to be glib, but meh--one more can't hurt.


How do others find the time?  I'm up early and put in long days. There is often weekend work. Around it all I must find time for family. There needs to be wind-down time and sleep in there somewhere.

Others do it. There are ways.  Give up a little time that's normally spent by myself anyway.

Why have I shared this?  Certainly it is therapeutic to a degree and I can refer to it in the future to push me forward.
But that's not my hope.

I want to reach someone else and push them forward. I'm an avid reader of blogs, sometimes churning through dozens a day. I make it part of my daily routine. I thoroughly enjoy reading what others have to say.

If you are like me, I'd like you to write--or write more.  

Because I'd like to read what you have to say.

Saturday, February 14, 2015


This year, after years of deliberation and encouragement from friends, I finally submitted a vExpert application.

I am honored and humbled to have been awarded vExpert for 2015 by VMware.  To be fair, I'm also rather ecstatic!

See the full list of stellar individuals at the official vExpert 2015 Announcement.

Sunday, November 9, 2014

vSphere Claim Rules with PowerCLI

We’ve been implementing HP 3PAR 7000 series into our environment. During this task we’ve tryied to be good admins by following the HP 3PAR StoreServ Storage and VMware vSphere 5 best practices.

Within this excellent resource there is a section for automating round robin policy for all 3PAR LUNs with a custom SATP rule.  That’s great, but it involves an esxcli command that must be run on each host:

For a small number of hosts that’s not too terrible--until you realize that you must either reboot each host or modify the policy for each LUN currently presented.  That’s not something that I’m likely to do.

With my aid of my technology buddy Google, I discovered several tidbits online:

  • Philip Sellers has a blog that works through much of this in PowerCLI.
  • Cormac Hogan has a blog that re-iterates the above, along with the commands required to unload each already claimed device (LUN), reload the claim rules, and rescan the HBAs.
Most of what I needed was out there already, of course. But I wanted to reload the claim rules in order to test the custom rule and without setting the policy individually on each LUN. I also didn’t want to impact every iSCSI LUN—just 3PAR—and there’s no need to reclaim a LUN that is already configured for round robin.

Here’s how I did it for each host:

Of course, I wrapped all of this around more PowerCLI that obtained a list of hosts in each cluster and managed the connections for esxcli.

If you receive any errors during the unclaim, make sure that your HA configuration is not using those LUNs as heartbeat datastores.  I experienced that problem which was easy to remedy in our environment.

Monday, June 30, 2014

Office 365 Staged Migrations with PowerShell

I have a love-hate relationship with PowerShell.  I want to love it and often do--except when my knowledge is lacking or it acts mysteriously (to me).
To aid my memory and perhaps help others, I've decided to post snippets as I continue my journey toward improving my PowerShell skills (I hear that shaking Luc Dekens' and Alan Renouf's hand at the same time increases one's PS Mojo).
With that out of the way, onward and upward.

We are in the midst of migrating from Exchange Server 2003 to Office 365 as a Staged Migration.  While not a particularly arduous task, it does involve pulling mailbox statistics and email addresses and using that information for the planning and creation of migration batches. It's tedious and error-prone.
Given a set of Exchange Servers, Domain Controllers, and a Universal Security Group, Get-MailboxSizes.ps1 generates a CSV containing mailbox names, server, size, number of items, office location, department, active mailbox flag, and string suitable for directly pasting into a Staged Migration CSV file.
2014-06-12 16_09_48-MailboxSizes

The ActiveMbx column is TRUE if the user is not enabled or a member of a Universal Security Group used for tracking progress and automating other things.

The odd column header at the last column should be directly pasted into your Staged Migration CSV file as row 1.  For successive entries, copy that column value in filtered rows as you plan the migration.   Please note that this column assumes Active Directory Synchronization with Office 365.

We've been known to paste entries from the last column into Notepad for a quick Search-Replace of ",,FALSE" with ";".  That yields a list that you can paste into the To field of a notification email or add members box of the Universal Security Group.

I’d like to thank Iain Brighton who lent a hand when I was stuck with Custom Objects. Yea Twitter!

Tuesday, September 4, 2012

Traditional DR…and its Imminent Demise?


Backhoe Damaging Underground Lines

My primary focus at VMworld 2012 was Disaster Recovery, which caused me to think a fair amount about the future of DR in general—it’s necessity, utility, and longevity.  Have we really escaped “traditional” DR?  Will the methods employed today exist as we know them in 10 years, or just be another integral part of the infrastructure?

Each session invariably started off comparing the “traditional” disaster recovery of yesterday against the virtualization-enabled DR of today, where the old machinations are replaced with flipping a software switch.

With the exception of American National Bank’s and Varrow’s Active/Active datacenter (INF-BCO1883), I can’t help but see this as still being traditional DR—only with today’s tools.

Let’s take a look at some of the main points in “traditional” DR versus today’s:

  • Before virtualization, restoring to the same hardware used in production was a challenge. If it could not be met, time was wasted.  Virtualization gives us a common hardware set, eliminating those hardware compatibility woes. 

    While a valid point, what if you could always purchase bland hardware, generic x86 servers at Wal-Mart as a commodity, like that which virtualization presents to the OS?
  • Tapes could not always be restored and took too much time. Virtualization gets us to replication technologies that avoid tape.

    Excluding array-based replication, disk-to-disk-to-tape solutions with replication were pitched as disaster recovery aids 10 years ago, specifically to get around the problems of tape.
  • New systems/applications required new servers.

    You got me there. Virtualization wins, and I’m happy with that.

Same process, new tools—albeit faster, better, stronger tools. It’s still traditional DR to me.

Now enter Cloud-based DR.  With DR in the cloud, there is no need to lease or require that which remains idle. In essence, keep an off-site copy of your data—a Good Thing anyway—and pay for what you need when you need.  Disaster Recovery has now moved fully from capex to opex.  It’s cloud being used for what cloud is intended. 

But not at the application level.

In an application-centric world, everything behaves like the modern applications to which we’ve become accustomed.  We are blissfully unaware, yet fully appreciative of Facebook, Google, Twitter, and the like spanning multiple datacenters.  We aren’t exposed to datacenter failures that they may encounter and we shouldn’t be. Nor should your customers. 

Your line-of-business systems need to be heading this way, today, for it is the key to availability across datacenters and devices (EUC was a big push at VMworld this year).  They shouldn’t care any more about what datacenter they occupy than how many instances are deployed.

The pieces are there. We’re seeing the increased popularity of orchestration with the likes of Chef and Puppet (in no particular order). Infrastructure manipulation via APIs such as Amazon provides into their Elastic Load Balancer.  Data—big or otherwise—replication, and sharding is becoming commonplace.

The hold-outs are back office systems that won’t get where we need them to be soon enough, yet demonstrate significant movement in this direction when you consider Office 365 and the like.

Once achieved, is expanding from private to public cloud based on increased load any different than contracting from one to the other based on availability?

Private, public, or hybrid the cloud is an extension of your datacenter. It’s the elasticity of your workloads at web-scale, that need not be within one datacenter.  If well orchestrated, you have “simple” contractions of your cloud based on not only load, but availability.

I see the agile system encompassing multiple datacenters at any point in time, expanding and contracting as load and availability changes. This, will be the new DR—no DR.  Just a well-designed modern system.

What are your thoughts?

Takeaway: Developers need to be aware of infrastructure; this could be interesting.