Category Archives: Windows

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Altaro VM Backup Review

logoWell you may be asking yourself what an EUC focused guy is doing reviewing a backup product, I’ll be honest, I wasn’t sure either but then something happened and I suddenly grew a strong appreciation for this product… but more on that later.

As one who still remembers (and has the scars) from those dreaded tape restore days to off site locations. I remember spending 72 hours + trying to restore machines to different hardware, struggle with different tape drive manufacturers and trying to find the right tape!  I jumped ship from sys admin long ago and moved to EUC, avoiding the backup market like the plague in later years so I really was a fresh set of eyes to this age old conundrum.

Recently I stumbled across Altaro VM backup as part of my usual day to day readings and my interest was piqued. Withstanding that as a home lab owner and a hypervisor snob I really only run vSphere and Hyper-V was normally not something I enjoyed working with… I got talking to a nice gentleman from Altaro and I was invited to join the closed beta for vSphere.

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ThinIO facts and figures, Part 4: Storage design and dangerous assumptions.  

Welcome back to this blog series discussing our new product ThinIO. Please find the below three earlier articles in this series:

In the final blog post in this series, we’re going to discuss storage design and a frequent problem face when sizing storage. Lets get right into it:

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ThinIO facts and figures, Part 2: The Bootstorm chestnut.

logoWelcome back! This blog post is part of a number of posts in advance of our upcoming release, for reference you can find part one below:

Getting right to it:

In this industry when somebody says ‘boot storms!’ – most of us will respond with:

image002

Boot storms are a well documented, boring problem and have many solutions available from vendors and hypervisors alike. Most solutions today rely on a ‘shared memory’ storage area to cache ‘on boot’, in theory caching only one startup or one pattern in order to then serve it back to the proceeding desktops to boot.

But why are boot storms an issue? While working on ThinIO we had the unique ability to really dive into the Windows boot process and analyse why boot storms cause the damage they do and in this post we thought we’d share our findings to better document the issue.

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Viewing open files on a file server from powershell.

/wp-content/uploads/2011/03/windows_powershell_icon.png?w=58&h=58&h=58So this is a situation you should all be aware of in an SBC / VDI environment, despite all warnings, you’ve redirected folders to your network drive and your file servers are screaming in agony?

Having been in this situation recently, I needed to audit and report on the types of files open on the file server, my hunch was a certain select number of users were running applications (like *gulp* lotus notes) from the network share.

Disappointed with the powershell scripts on the interwebs, I decided to write my own function to perform this task:

[sourcecode language=”powershell”]
function get-openfiles{
param(
$computername=@($env:computername),
$verbose=$false)
$collection = @()
foreach ($computer in $computername){
$netfile = [ADSI]"WinNT://$computer/LanmanServer"

$netfile.Invoke("Resources") | foreach {
try{
$collection += New-Object PsObject -Property @{
Id = $_.GetType().InvokeMember("Name", ‘GetProperty’, $null, $_, $null)
itemPath = $_.GetType().InvokeMember("Path", ‘GetProperty’, $null, $_, $null)
UserName = $_.GetType().InvokeMember("User", ‘GetProperty’, $null, $_, $null)
LockCount = $_.GetType().InvokeMember("LockCount", ‘GetProperty’, $null, $_, $null)
Server = $computer
}
}
catch{
if ($verbose){write-warning $error[0]}
}
}
}
Return $collection
}
[/sourcecode]

The function above (get-openfiles) has been written to accept an array of servers to the command line and it will return the following items:

  • The ID of the open file.
  • The server it’s open from.
  • The username who has the file open.
  • The amount of locks the file has.

A couple of quick examples for using this command are below:


Retrieving open files from server1:


full

[sourcecode language=”powershell”]get-openfiles -computername server1 | select server,itempath,lockcount[/sourcecode]



Retrieve a count of open files that end with the nsf file type (Lotus Notes):


count

[sourcecode language=”powershell”](get-open files -computername server1,server2 | ? {$_.itempath -like "*.nsf*"}).count()[/sourcecode]



Retrieve a report of total open files on a number of file servers:


report

 

[sourcecode language=”powershell”]get-openfiles -computername server1,server2,server3,server4,server5 | group -property server[/sourcecode]

 

Monitoring Storage disk queue’s and IO with PowerShell

/wp-content/uploads/2011/03/windows_powershell_icon.png?w=58&h=58&h=58Here’s one that used to bother me alot. The problem usually went as follows:

“Your XenApp servers have very high disk queue’s and IO”

“What’s causing it?”

“dunno…”

With Server 2008, the task manager’s resource monitor feature will help you find these items. But in server 2003 this was a perilous task. The specific details for disk io per process are stored in performance monitor under each specific process running. Trying to analyse each process was a massive pain, but powershell can do some very clever work to help alleviate this!

I wrote two quick functions which act similar to “top” in linux for giving an on screen view, updating at interval of what exactly is creating IO activity. These two functions are:

get-IODataBytes:

storageio

Get-IODataOperations

storageioops

The code for these functions are below:

[sourcecode language=”powershell”]
function get-iodatabytes{
$result=(get-counter -counter "Process(*)IO Data Bytes/sec" -ea 0).countersamples | ? {$_.cookedvalue -gt 0} | select instancename,@{Name="SessionID";Expression={if ($_.path.contains("#")){($_.path.split("#)"))[1]}else{"0"}}},@{Name="IO Data Bytes/sec";Expression={[math]::Round($_.cookedvalue,0)}},@{Name="IO Data KBytes/sec";Expression={[math]::Round($_.cookedvalue / 1024,0)}} | sort -Descending "IO Data Bytes/sec" | ft
$currentqueue=(((get-counter -counter "PhysicalDisk(0 C:)Current Disk Queue Length" -ea 0).countersamples) | select cookedvalue).cookedvalue
clear
write-warning "Hit [CTRL] + [C] to exit live capture"
write-host "Current Disk queue: $currentqueue"
return $Result
}

FUnction get-IODataOperations {
$result=(get-counter -counter "Process(*)IO Data Operations/sec" -ea 0).countersamples | ? {$_.cookedvalue -gt 0} | select instancename,@{Name="SessionID";Expression={if ($_.path.contains("#")){($_.path.split("#)"))[1]}else{"0"}}},@{Name="IO Data Operations/sec";Expression={[math]::Round($_.cookedvalue,0)}} | sort -Descending "IO Data Operations/sec" | ft
$currentqueue=(((get-counter -counter "PhysicalDisk(0 C:)Current Disk Queue Length" -ea 0).countersamples) | select cookedvalue).cookedvalue
clear
write-warning "Hit [CTRL] + [C] to exit live capture"
write-host "Current Disk queue: $currentqueue"
return $Result
}

[/sourcecode]

if you wish to loop one of these functions, simply use the following code:

[sourcecode language=”powershell”]
while ($true){
get-iodataoperations
start-sleep 1
}
[/sourcecode]