HP Storage Essentials NAS Manager Software - Manual (Page 409)

Storage Essentials 5.1 User Guide 377
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 377
• ” Host Security Group Names on HDS Storage Systems ” on page 377
• ” Unable to Provision When HDS CruiseControl Is Enabled ” on page 378
• ” Increasing the Wait Time for the Management Server ” on page 378
• ” Initiator Ports Cannot Be Used for Provisioning ” on page 379
• ” The Software Is Unable to Map a Host to Volumes in Different Host Storage Domains of the
Same Port on HDS 9900V ” on page 380
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.