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

 

 

Storage Essentials 5.00.01 User Guide 329