Here is a little test.  Check your documentation:   Do you know how to power down and power up the equipment in your computer room?   If you had to power off your site in a hurry would you know how?   If you wanted to script a shutdown, could you do it?

Here are some hints and tips that might help you with some of my favourite products:

DS8000

The process to power up or down your DS8000 is documented in the Information Center here.

Scripted shutdown

If you want to script powering off a DS8000 storage unit you can use the chsu -pwroff DSCLI command.   This command will shut down and power off the specified DS8000 unit.  Be careful before powering off the unit to ensure that all I/O activity has been stopped. An example of the command is shown below.   Your machine will have a different IP address, password and serial number to mine.  Note the serial number always ends in zero because we send the command to the storage unit.

dscli -hmc1 10.1.60.240 -user admin -passwd passw0rd chsu -pwroff -dev IBM.2107-75DC710

It takes over a minute before you will see any change in the machine.  So be patient.  The HMC will not power off.   You can either leave it powered on or shut it down manually.

To power the DS8000 back on, use the  chsu –pwron command:

dscli -hmc1 10.1.60.240 -user admin -passwd passw0rd chsu -pwron -dev IBM.2107-75DC710

Storwize V7000 and SVC

The Storwize V7000 Information Center explains the process to power down here and power up here.

The SVC Information Center explains the process to power down and up here.

I created a short video on how to shutdown your Storwize V7000 using the V7000 GUI. You can view it on Youtube:

First and foremost, the design of the XIV GUI (that has inspired such dramatic change in IBMs other GUIs), was made possible, not by clever XIV GUI developers (don't get me wrong - they ARE clever), but by a remarkably user-friendly architecture.  The XIV GUI is a miracle of ease-of-use for end users, made possible because first and foremost, by design, the XIV made it almost impossible to make it hard.

The good news for Storage administrators, is that unlike a jet aircraft, where a pilot needs to spend hundreds of hours in the cockpit before they are considered potentially competent,  the XIV GUI can be picked up in minutes and lends itself very well to casual contact.   You don't need to keep using it to stay competent.

The challenge for IBM was take more complex products, which require more user decisions, and make the usage experience just as easy.   To add to this, the SVC and DS8000 GUIs were driven by WebSphere.   Changing these GUIs would require a complete re-write to employ Java script.

First off the rank was the SVC and Storwize V7000.   With the release last year of the SVC 6.1 update, the transformation was nothing less than remarkable.   End user experience ruled every decision.   The key again is that the user does not need to spend hundred of hours learning this GUI or re-learning it every time they go to perform a configuration task.   Everything is in its right place.  Its much more than an XIV-like GUI.   Its a GUI that took the ease of use experience of the XIV and used that to inspire something just as remarkable.

With the release of the 6.1 update for the DS8000, we complete another fundamental step towards a truly common GUI.   The DS8000 GUI has undergone a complete re-write.   Essentially it has been rebuilt from the ground up.   This highlights something fundamental:   It confirms the DS8000 has a very strong roadmap.

As you can see from the image below, the transformation from the old design (to the left) to an ease of use model is complete:

The end result is  a DS8000 GUI that has the same look and feel that we find in the XIV, the Storwize V7000 and the SVC.  It is a GUI packed with usability features and because we use Javascript, the webpages are active and  self-refreshing.

In short it a common flight deck, that almost anyone can fly.

Disk Partition Alignment (Sector Alignment): Make the Case: Save Hundreds of Thousands of Dollars
http://blogs.msdn.com/b/jimmymay/archive/2009/05/08/disk-partition-alignment-sector-alignment-make-the-case-with-this-template.aspx

How to Align Exchange I/O with Storage Track Boundaries
http://technet.microsoft.com/en-us/library/aa995867(EXCHG.65).aspx

Disk performance may be slower than expected when you use multiple disks in Windows Server 2003, in Windows XP, and in Windows 2000
http://support.microsoft.com/kb/929491
Disk Partition Alignment Best Practices for SQL Serverhttp://msdn.microsoft.com/en-us/library/dd758814(v=sql.100).aspx

Back already?   Hopefully you now know that  disk partition alignment is all about starting an IO at a logical block address that best matches how the underlying hardware stores your data.   So now your wondering, what does this have to do with XIV?  Well XIV has two concepts that relate to this:  cache and partitions.

XIV cache (the server memory used to speed up reads and writes) is organised into 4 KB blocks (which is nice and small).

So the XIV cache does not care about disk alignment.

But when it comes to writing and read from disk, the XIV writes data into chunks of consecutive logical block addresses (LBAs) that we call partitions.  These partitions are 1 MiB in size. What does that concept mean?  It means the magical number for XIV is 1024 KB or 1 MB.  (actually KiB and MiB, but for the sake of ease, I will stick to the naming used by Microsoft.   Given this number is fairly large (other hardware often aligns to 32KB, 64KB or 256KB), for XIV this reduces the potential impact of misaligned partitions.   Which is good.

BUT....

Correct Windows Disk Alignment could give up to  a 7% performance improvement when using an offset of 1024 KiB. (1 MiB).  I need to be clear, that's not a guaranteedimprovement of 7%.  It's a maximum possible improvement.  Your particular server will see an improvement somewhere between 0% and 7%.   It depends on your workload patterns.  The more small and random your workload, the more useful setting the 1024 KB offset will be.  The more sequential your workload, the less useful it will be,  as only the first and last parts of an I/O could potentially be misaligned.  This mis-alignment could equate to a tiny percentage of extra work for the XIV.   Sadly there is no metric you can display to detect how much impact misalignment is actually having.

So should you do it?   The good news is that new volumes created under Windows 2008 prefer the 1 MB boundary.  So a fresh install should already be using the correct values. The bad news is that volumes created under earlier Windows Operating Systems (Such as Windows 2000 and 2003) will almost certainly be misaligned, and correcting the alignment is destructive to the data in the partition.

How to check alignment at the host?  Here is an example:

I start diskpart:

C:\Windows\system32>diskpart
Microsoft DiskPart version 6.1.7600
Copyright (C) 1999-2008 Microsoft Corporation.
On computer: ANTHONYV-PC

I list my disks.  In this example I have two disks installed in my laptop.  I select disk 0:

DISKPART> list disk
 Disk ###  Status         Size     Free     Dyn  Gpt  
 --------  -------------  -------  -------  ---  ---  
 Disk 0    Online          238 GB  5724 MB  
 Disk 1    Online          232 GB  1024 KB
DISKPART> select disk 0
Disk 0 is now the selected disk.

Now I list the partitions and see the offset for each one.

DISKPART> list partition
 Partition ###  Type              Size     Offset  
-------------  ----------------  -------  -------  
Partition 1    Primary            100 MB  1024 KB  
Partition 2    Primary            232 GB   101 MB

Partition  1 has an offset of 1024 KB, which is 1 MB, which is perfect for XIV.   Partition 2 has an offset of 101 MB, which is still on the 1MB boundary (it was pushed there by the combination of the size of the first partition (100 MB) and its offset (1 MB).   So this is perfect.

For an example of how to create a partition with the correct offset, check out this how-to document, that also provides some good follow on reading:
http://www-03.ibm.com/support/techdocs/atsmastr.nsf/WebIndex/WP101758

What about other IBM products?

The IBM SVC and Storwize V7000 prefers 64 KB (or larger) offsets as documented here:
http://www-01.ibm.com/support/docview.wss?uid=ssg1S1003291 
Why?   Because the SVC and Storwize V7000 use a concept of grains, where each grain is usually 64KB or 256KB in size.

The DS8000 (regardless of model), also prefers 64 KB offsets.  The DS8000 use the concept of logical tracks where each logical track is 64KB.

The DS3000/DS4000/DS5000 range allow the user to set the segment size of a logical volume on creation.  The setting that you define should match the segment size defined for the logical drive being used.  In the example below, it is 64 KB.

What about VMWare?  

The answers are no different.   Misalignment can indeed make a difference to client performance.    Check this link from NetApp and this document from VMware:   

http://www.vmware.com/resources/techresources/608 

For an EMC perspective, check out this link from someone I respect a great deal, Chad Sakac:
http://virtualgeek.typepad.com/virtual_geek/2010/06/so-why-all-the-fuss-about-alignment.html

I searched around looking for an image to highlight the theme of alignment.   I found this image in the IBM archives for the IBM Mass Storage Facility announced back in 1974. I am sure this product had some interesting alignment challenges.