SVC to V7000 Migration

Hello all, for those of you wondering, yes I am still alive! I apologise for going AWOL for 6 months! However I am now back and hope to be regularly updating my blog with all my experiences and findings e.t.c. 

So whats the story? Back in 2010 IBM released the Storwize V7000 and subsequently the Storwize V7000 Unified. The IBM Storwize V7000 is IBMs next generation mid-range storage Virtualization platform. The platform has been built utilising many features from IBMs best of breed solutions including SVC, DS8000 and XIV. The features list is huge and my favourites include Easy Tier, the Dynamic Migration capabilities, the External Storage Subsystem Virtualization capabilities (these are not vendor limited - V6.3 Supported Hardware List, Device Driver, Firmware and Recommended Software Levels for IBM Storwize V7000) VAAI integration, vCenter integration and Clustered Systems. In a sentence it's a solid mid-range storage subsystem containing many features you would only expect to see on an enterprise level storage subsystem.

Data migration from an SVC presenting a DS3k, DS4k & DS5k to a V7000. It looks simple doesn't it? However I recently came across a scenario with an environment running old 4F2 SVC nodes and planned to migrate all data under the SVC on DS3k, DS4k and DS5k storage onto a V7000. This presented a problem in that the V7000 can only be presented as a host to an SVC running 5.1.0.8 and above - V5.1.x - Supported Hardware List, Device Driver and Firmware Levels for IBM SVC A quick check over the Node and UPS Interoperability Matrix for SVC shows that the 4F2s are only compatible with SVC code level 4.3.x. 

Hmmmm so what now? If you are running any of the SVC nodes - CG8s, CF8s, 8A4s, 8G4s, 8F4s and 8F2s. I suggest you upgrade from 4.3.x to a minimum of 5.1.0.8. The upgrade process from 4.3.x to 5.1.x takes approx 1 hour, ensure you complete the required planning prior to upgrading the system If you are feeling adventurous I would follow this upgrade process to get the SVC running the latest code release 4.3.x.x >> 5.1.0.11 >> 6.3.0.2. Once upgraded to 5.1.0.8 or higher you can follow these steps to migrate the VDisks under your SVC onto the V7000:

• Create the V7000 as a host on the SVC 
• Create the relevant pools of MDisks on your V7000 
• Create the SVC as a host on the V7000 
• Create replica sized VDisks on the V7000 as per the VDisks currently presented via your SVC 
• Present the VDisks on your V7000 to the SVC 
• Export SVC VDisks to Image Mode on the matching VDisks created on the V7000 
• Upgrade SDDSM drivers 
• Shutdown host
• Remove SVC VDisk mapping to host 
• Remove V7000 VDisk mapping to SVC 
• Map V7000 VDisk to same LUN number on host 
• Start up host, confirm via datapath querys that the relevant drives and paths are connected to the host via the V7000 

However if you have 4F2 nodes or you have change limitations in place and cannot run or upgrade to 5.1.0.8 or higher on your SVC the migration process becomes slightly more difficult.

The only option (I can see) for migration of physical hosts accessing VDisks on 4F2 SVC nodes running 4.3.1.11 is to migrate the VDisks on the SVC to image mode (on supported swing kit) and then import these VDisks under the V7000. The high level migration process for a 4F2 SVC cluster presenting DS3k, DS4k and DS5K is detailed below:

• Create identically sized VDisks on the array being used as the Swing Kit as per size of VDisk which is going to be migrated to Image Mode on the SVC **Ensure you spread the LDs across the muliple arrays and controllers on the swing kit (if possible) and provision the storage on the swing kit with sufficient redundancy as production data will be temporarily running on the swing kit.
• Map the Logical Drive to Host Group SVC
• Once the Drive has been mapped, login to the SVC and select Work with Managed Disks >> Discover MDisks
• The newly Presented MDisk should then be discovered in an online state and Unmanaged mode
• Create an MDisk group for the Swing Kit
• On the SVC select Work with Virtual Disks, Virtual Disks, select the VDisk that is going to be migrated to an Image Mode VDisk and select Migrate to an Image Mode VDisk
• Confirm the copy to migrate to the Image Mode VDisk
• Select the Target MDisk which is the MDisk presented up from the temporary array
• Select the MDisk Group which will be the MDisk group previously create
• Confirm the number of threads to devote this process (The default is 4 which makes the process the highest priority - this can be changed to prioritise simultaneous migrations) 
• Verify the Migration Attributes and once confirmed they are correct, select finish
• Now go to manage progress, view progress, Image Mode Migration and click on refresh then the progress % to view the detailed progress info of the of migrating data from a virtual disk (VDisk) to an image mode VDisk
• Once the conversion is complete the VDisk will be displayed an image mode VDisk
• Logon to the server and confirm the SAN drives are visible and all applications accessing data on these drives are accessible
• Logon to host
• Confirm if host OS is x86 or x64
• Open command prompt and run datapath query device from within current SDDSM installation directory and take a note of the output
• Update SDDDSM driver to latest V7000 Driver
• Once completed the SDDDSM driver installation prompts for a reboot.
• Once host has been rebooted confirm that the host boots successfully
• Shutdown host
• Edit Host to Logical Drive Mapping on DS Storage Manager
• Prior to changing the mapping ensure you take a note of the LUN ID
• Remove mapping of LD to SVC
• Select Create Host-to-Logical Drive Mappings 
• Select Host Group V7000 (you will need to create this on DS Storage Manager)
• Select Logical Drive containing image mode VDisk
• Ensure the same LUN number is used when presenting the LD to the V7000
• Select Finish- Confirm the LD is now mapped to Host Group V7000
• Login to the V7000, select external storage subsystems and select array presented to the V7000 containing image mode VDisk, detect MDisks
• The LD should be detected as an MDisk
• Right click the MDisk and select import
• Confirm the default settings (Import as generic volume and Enable Caching and select next)
  **DO NOT SELECT A POOL TO MIGRATE THE MDISK INTO**
• Select Finish - You will be informed that the volume will be placed in a temporary migration storage pool. Select Ok to continue
• The Import MDisks task will then complete
• The MDisk mode is now Image rather than Unmanaged
• On the V7000 go into volume and you will see a new volumes within Storage Pool MigrationPool_xxxx
• Rename the imported VDisk from controller1_xxxxxxxxxxxxxxxxxx to original VDisk name on SVC 
• Right click volume and select map to host. Chose the relevant Host and change the SCSI ID to the LUN ID documented previously
• Select Map Volumes and the V7000 will complete the volume mapping to the Host
• Boot the Host and confirm it comes up successfully and the Image mode VDisk on the Swing Kit is visible
• Login to V7000 >> Go to Volumes >> Right click the Volume you wish to create a VDisk Mirror for (this will be within MigrationPool_xxxx) select Volume Copy Actions >> Add Mirrored Copy
• You are then prompted to Select the Volume Type & Storage Pool for the VDisk Mirror >> Once confirmed the Add Volume Copy task then starts and completed
• Refresh the Volumes page and you will note that two copies exist under volume. Copy0 is within Storage Pool MigrationPool_xxxx and Copy1 within Storage Pool you specified when creating the VDisk mirror. During the Volume Syncronization Copy0 is the primary volume this is shown by the * at the end of the Copy Volume Name
• Logging onto the host if you run a datapath query device as expected will see the host can see two devices (the array containing the Image Mode VDisk & V7000)
• Once the volume synchronization for the VDisk mirror completes, confirm Volume Mirrors are in Sync
• Promote Striped Volume (V7000 Internal to Primary)
• Stop all IO on Host
• Re-Activate Disk on Host
• Delete Image mode volume from mirror
• Remove the mapping of the VDisk Image mode volume via Storage Manager
• Reboot Host
• Re-Activate Disk on Host following device ID change
• Reboot Host
• Confirm Host comes online and all applications are accessible 

Hurrah you are now successfully migrated onto your V7000. Its also worth noting that you will want to complete the following tidy up tasks following the successful migration of a VDisk:

• Delete VDisk to Host Mapping on SVC for Migrated VDisk
• Delete the VDisk that has been migrated onto the V7000
• Delete Host on SVC once no VDisks are being presented to the host via the SVC
• Delete the zones within the Fabrics associating the SVC to the Host that no longer has any associated VDisks
• Delete the Logical Drive containing the VDisk Image on the Swing Kit

Fortunately the migration path for virtual machines using Storage VMotion is a lot simpler and involves No Downtime! (Providing you are running on ESX 3.5 or above, if you are still running 3.5 you will need to run the SVM interactively via the CLI, via the remote CLI or the SVM VI Client plugin) To complete the SVM you will need to present the VDisks provisioned for ESX/ESXi datastores up to your ESX Host Group on the V7000 and SVM the VMs to the new storage. If you are running vSphere 5 you can also take advantage of creating fresh VMFS5 datastores on the V7000 and SVM from your old VMFS3 datastores onto these. 

I hope this makes sense and helps all of you who cannot upgrade your SVC past 4.3.x and are looking to migrate onto V7000. If your confused or need more information on the V7000/V7000U and getting your environment successfully migrated onto these please feel free to comment on the blog or contact me via wbush@virtualvizion.com