In the PowerVM environment, if you want to improve storage utilization or use advanced features such as Live Partition Mobility (LPM) and Simplified Remote Restart (SRR) you are going to go down the path of storage virtualization. Traditional setups require you to create client adapters (Virtual SCSI or Virtual FC) in the partition, a server adapter in the Virtual IO Server (VIOS) and then use another set of tools to map it all together. That is a lot of context switching. Things get even more complicated if you are using a Logical Volume or Logical Unit from a Shared Storage Pool since you have to create the Logical Volume or Logical Unit prior to mapping the storage.
The comment, "All I wanted to do was add some storage to my partition"... hit home. We thought about the time & effort spent in configuring virtual storage and how to simplify the process for you. The answer was obvious... code should be able to handle most of this leaving the operator to only worry about attaching the storage in the partition. The back-end nitty-gritty work would be handled for you (Advanced users needn't worry; there are tunables to work with).
The HMC Enhanced UI provides simplified ways to work with Virtual Storage. The GUI provides an integrated and consolidated view of all virtual storage devices assigned to the partition and allows you to add/remove storage in one step. It can also create Multi-Path IO (or redundant paths) when adding storage.
In this Blog, we will walk you through the Virtual Storage flow with the HMC Enhanced UI with steps to add/remove storage and the advanced options which you could use.
Partition Virtual Storage Panel
You can view virtual storage for a partition by navigating to “Virtual Storage” option available on left side after clicking on the required partition as shown in Figure 1.
Resources ► All Systems ► <system name> ► Partitions ► <partition Name> ► Virtual Storage
View Virtual Storage
Partition storage details can be checked from two perspectives: a) Storage View b) Adapter View
a) Storage View
It shows the end to end view of storage devices associated with a client partition
View Virtual SCSI
This is the landing page once the Virtual Storage option is clicked (as shown in Figure 1). This panel lists all Virtual SCSI backed by
- Physical Volume
- Shared Storage Pool Volume
- Logical Volume
View Virtual Fibre Channel
It lists all Virtual Fibre Channel (VFC) resources assigned to a client partition showing client device name, associated VIOS , server location code and WWPN pair as shown in Figure 2.
b) Adapter View
This view shows the details of server and client adapter pair per VIOS for SCSI and FC adapters that are allocated for the logical partition. This view provides a mapping of adapters to the physical device for a partition. E.g. It shows slot numbers, client device name and device type and size for SCSI adapters as shown in Figure 3.
Add Virtual Storage
To add a virtual storage device, you have to select storage device and connected VIOS's and we will get the storage mapped for you. HMC will create server and client adapters and mapping internally as a part of this operation.
Add SCSI Storage
Click on “Add Virtual SCSI Storage” button (as shown in Figure 1) to add storage backed by SCSI adapter. This button is enabled only if
- RMC connection for at least one VIOS is active. And
- RMC connection is active for an active partition or Partition is inactive
It opens a new screen as shown in Figure 4. Select the required option for choosing the backing device. By default, it shows Physical Volume as backing device (We will show you a flow for adding a “Shared Storage Pool Volume” as backing device to explain the “Add” operation here).
Add SCSI backed by New Shared Storage Pool Volume
Choose "Add new Shared Storage Pool Volume" option if you want to create a new logical unit and map it to the partition (Figure 4)
- Select the size and VIOS to enable the “Edit connection” button.
- Tier and Device Name can be changed if required.
Add SCSI backed by Existing Shared Storage Pool Volume
Choose "Add existing Shared Storage Pool Volume" if existing Logical Unit can be used to add SCSI adapter. On selecting this option, it displays all existing SSP pool volumes in a table, as shown in Figure 5.
Show Assigned Shared Storage Pool Volume: On selecting this, it lists SSP pool volumes already in use. This is useful if the same logical unit has to be shared across multiple partitions for High Availability.
Edit Connection: This button is enabled once you select one device and one VIOS. On clicking "Edit connection", you can choose the slot numbers for Server Adapter as shown in the Figure 6.
Click the "OK" button to go back to previous screen and then again select "OK" to complete the “Add” operation. Once the operation completes successfully, the newly added storage device will get reflected in the virtual storage panel.
Add Fibre Channel Adapter
On “Virtual Fiber Channel” tab, click on “Add Virtual Fiber Channel Device” button (as shown in Figure 2). The new window lists all Fibre Channel ports per VIOS (Figure 7).
"Edit Connection" can be used to specify WWPN pair, if required. Otherwise the WWPN pair will be auto generated.
Remove Virtual Storage
To remove any virtual storage adapter, select the required storage and click on Action Menu button to select the “Remove” option from the displayed options. This option may not be available based on RMC connection as explained in "Add" operation.
On selecting “Remove option”, it pops up the window for confirmation. Once "OK" is pressed, it removes the storage and also its associated adapters.
Partition Virtual Storage Topology
You have now attached storage to the partition, however you would like to know how the partitions are connected to the storage via the VIOS and also to the physical adapters; i.e., the information you need for an end-to-end view to be shared with the team or your storage admin. Well, we have a simple way for you to achieve that. You can view the partition virtual storage topology diagram by navigating to the partition and selecting "Partition Virtual Storage Diagram" under Topology section. The topology view provides end-to-end view of the storage starting from the client device to the client adapter to the server adapter to the storage device to the physical adapters. You can export the diagram as a PDF or PNG as well if you would like to view them offline or share it with your team or admins.
The HMC Enhanced UI's Virtual Storage provides simplified and easy to use interface to work with storage for a partition where a user can work with storage without worrying about the client and server adapters. While we are continuously working on improving the usability (and performance), we would like to get your feedback.
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