HP Storage Essentials NAS Manager Software - Manual (Page 359)

Storage Essentials 5.00.01 User Guide 329
3. In the right pane, click the Provision button corresponding to the storage system in which you
want to access information about volumes.
4. Click Step 2 Volume.
5. Click the Edit button ( ) corresponding to the volume you want to modify.
6. Type the cache read ahead multiplier (0 to 65535 bytes) in the Cache read-ahead multiplier
field.
A cache read ahead multiplier copies additional data blocks into the cache while it is reading
and copying host-requested data blocks from disk to cache. To disable this option, type 0.
7. (Optional) Select Read Caching.
When this option is enabled, the host's operations are stored in controller cache memory.
8. (Optional) Select Write Caching.
When this option is selected, data is written to the cache memory of a controller
9. (Optional) Select Write Caching with Mirroring.
Use this option to preserve data if a controller or the cache fails. When this option is enabled,
the data is written to two redundant controllers of the same cache size. This configuration
provides redundancy in case a controller fails. One controller performs uncompleted write
operations when the other controller fails.
10. To change the current owner, select a new owner from the Current Owner drop-down menu.
11. Click OK.
Rules for Creating Host Security Groups
The management server now uses host security groups instead of LUN masking and LUN mapping.
With the introduction of host security groups, the management server has a new definition of
mapped for this release. Mapped is capacity that is accessible by one or more hosts external to the
array (aggregated capacity of volumes that are accessible from hosts external to the subsystem).
The number of initiators allowed in the HSG depends on the type of storage system:
Table 50 Allowed Initiators in Host Security Groups
Storage System Allowed Initiators in HSGs
EMC CLARiiON 0 or more initiators
Engenio (LSI) 0 or more initiators
HDS 0 or more initiators
HP EVA and MSA 0 or more initiators
IBM only one initiator per host security group
Sun 35xx One initiator per host security group
Sun 6920 only one initiator per host security group
Sun 6130 0 or more initiators