HP Logical Server Management Best Practices

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Storage pool entry considerations
There are a variety of ways logical server storage pool entries can be used, and the server administrator should
balance the value of multi-pathing, support for multi-initiator NPIV, the need for multiple logical servers to access the
same data volumes, and the convenience of OS installation techniques. Consider first the need for multi-pathing.
Many customers have requirements to configure multiple paths to boot and data volumes. This is done by having
multiple HBA ports on each logical server connect to separate SAN fabrics which connect to separate controllers on
the disk arrays presenting the required boot and data LUNs. Figure 16 shows Logical Server A with such connectivity.
The logical server software has allocated WWNs for the HBA ports, and the logical server storage pool entry
contains information about two volumes, one boot and one data, each presented to both HBA WWNs over both
array controllers, routed though two SAN fabrics.
Figure 16: A logical server with redundant HBA ports, SAN fabrics, and storage controllers
A later section of this white paper describes how the Insight Control server deployment solution (formerly known as
Rapid Deployment Pack) OS deployment jobs can be adjusted to ensure the OS image is appropriately installed on
the boot volume. Alternatively, the storage pool entry can contain just the boot volume until OS installation is
complete, and then the data volume(s) can be added to the entry, presenting the volumes to the same set of WWNs
for redundancy. This does require another interaction with the storage administrator; faster provisioning with only a
single storage administrator interaction is achieved by adjusting the HP Insight Control server deployment jobs or
having boot and data volumes presented to different sets of WWNs (either in one storage pool entry, or separate
storage pool entries). The use of multi-initiator NPIV greatly facilitates presenting volumes to separate initiator WWNs
(and then combining those various initiator WWNs onto physical HBA ports). More detail regarding multi-initiator
NPIV is available in the Matrix operating environment - Automated Storage Provisioning: “Static” SAN volume
automation via multi-initiator NPIV white paper available at http://www.hp.com/go/matrixoe/docs.
When multiple logical servers are to share a common data volume, that volume is represented in a single storage
pool entry with multiple sharers specified. For multi-path access to the shared data volume, two sharers would require
four WWNs (shown as C, D, G, and H in storage pool entry 2 of Figure 17). The logical server software will allocate
enough WWNs to handle the number of sharers desired, and those WWNs can be applied to HBA ports of the
logical servers. Each logical server would have multiple storage pool entries; the shared data volume entry and a
private boot volume, as shown in Figure 17. Note that four logical HBA ports are required for each logical server to
have multi-pathing to the private boot volume and shared data volume. With multi-initiator NPIV, those four logical
ports may map to two physical HBA ports. Without multi-initiator NPIV, an additional HBA would be required to have
four physical ports. Without multi-pathing, this configuration can be done with two HBA ports per logical server.
vdisk 1
vdisk 2
Array A
C1
C2
Fabric B
Fabric A
HBA Port 1 50:06:0B:00:05:02:00:3D
HBA Port 2 50:06:0B:00:05:02:00:3E
Logical
Server A
1
2
vdisk 1 is a 5 GB boot volume,
Windows; present over both
array controllers, both fabrics, to
both ports of logical server A
vdisk 2 is a 40 GB data volume,
Windows, present over both
array controllers, both fabrics, to
both ports of logical server A
Volume 1, Port 1 WWN, primary boot, Storage WWN C1, LUN 0
Volume 1, Port 2 WWN, secondary boot, Storage WWN C2, LUN 0
Volume 2, Port 1 WWN, Storage WWN C1, LUN 1
Volume 2, Port 2 WWN, Storage WWN C2, LUN 1
Logical Server Storage Pool Entry
Volume 1
5 GB boot,
Windows
Volume 2
40 GB data,
Windows
vdisk 1
vdisk 2
Array A
C1
C2
vdisk 1
vdisk 2
Array A
C1
C2
vdisk 1
vdisk 2
Array A
C1
C2
Fabric BFabric B
Fabric AFabric A
HBA Port 1 50:06:0B:00:05:02:00:3D
HBA Port 2 50:06:0B:00:05:02:00:3E
Logical
Server A
1
2
vdisk 1 is a 5 GB boot volume,
Windows; present over both
array controllers, both fabrics, to
both ports of logical server A
vdisk 2 is a 40 GB data volume,
Windows, present over both
array controllers, both fabrics, to
both ports of logical server A
Volume 1, Port 1 WWN, primary boot, Storage WWN C1, LUN 0
Volume 1, Port 2 WWN, secondary boot, Storage WWN C2, LUN 0
Volume 2, Port 1 WWN, Storage WWN C1, LUN 1
Volume 2, Port 2 WWN, Storage WWN C2, LUN 1
Logical Server Storage Pool Entry
Volume 1, Port 1 WWN, primary boot, Storage WWN C1, LUN 0
Volume 1, Port 2 WWN, secondary boot, Storage WWN C2, LUN 0
Volume 2, Port 1 WWN, Storage WWN C1, LUN 1
Volume 2, Port 2 WWN, Storage WWN C2, LUN 1
Logical Server Storage Pool Entry
Volume 1
5 GB boot,
Windows
Volume 2
40 GB data,
Windows
Volume 1
5 GB boot,
Windows
Volume 2
40 GB data,
Windows