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Issues specific to hds storage systems, About provisioning on hds storage systems – HP Storage Essentials NAS Manager Software User Manual

Page 373

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Storage Essentials 5.00.01 User Guide 343

If a provisioning failure has caused the Symmetrix storage system to remain locked, you are alerted

to this situation in Event Manager and on the Properties tab. You may receive a message resembling

the following:

Unable to end device masking session. Symmetrix '000001835005700' may be
locked.

Some EMC Volumes, Their LUNs and LUN Maskings Are Hidden

EMC volumes, their LUNs and LUN maskings for the volumes that play a special role (such as

holding device masking information, attached BCVs, gate-keeper devices) are hidden. On the host

side, the software shows LUN maskings for these volumes. So you may see a LUN masking, but not

its volume residing on the EMC storage system.

Issues Specific to HDS Storage Systems

This section describes issues specific to HDS storage systems.

About Provisioning on HDS Storage Systems

” on page 343

Unable to Provision When HDS CruiseControl Is Enabled

” on page 343

Increasing the Wait Time for the Management Server

” on page 344

Initiator Ports Cannot Be Used for Provisioning

” on page 345

The Software Is Unable to Map a Host to Volumes in Different Host Storage Domains of the

Same Port on HDS 9900V

” on page 345

About Provisioning on HDS Storage Systems

IMPORTANT:

The management server does not allow LUSE of different RAID levels.

HDS ships some of its storage systems with volumes already created. When the software first

discovers an HDS storage system, it detects the volumes created by HDS. When you use the

software's “create a volume” feature, you are assigning the already created volume.
The software does not delete volumes created by HDS. When you use the software's “delete a

volume” feature, the software marks the volume as hidden in its repository. These “hidden volumes”

are stored in the “Free LDEVs“ list.
If you use an LDEV in the “Free LDEVs” list when you create a volume, the LDEV is removed from the

“Free LDEVs” list. The LDEVs was moved from the list because it is now assigned.
HDS cannot create a LUSE volume (made up of multiple LDEVs) without mapping it to a target port

(that is without creating a LUN). In the software, creating a volume and creating a LUN are two

different operations. Therefore, the software keeps the volumes, made from multiple LDEVs in the

“Grouped LDEVs“ list in the repository. Once these volumes are mapped to the target port and a

LUN is created for them, they are removed from the repository and a real LUSE volume is created on

the HDS box.
For example, assume you have several 2-GB “Free LDEVs” and you want to create a 4-GB volume.

Since the request is larger than an LDEV, two of the “Free LDEVs” will be used for the 4-GB volume.