A storage domain, also called a set or a storage partition, is a logical entity used to partition storage. To create a storage domain after volume creation, you must define a single host or a collection of hosts (called a host group) that will access the storage array. Then, you will need to define a volume-to-logical unit number (LUN) mapping, which will allow you to specify the host or host group that will have access to a particular volume in your storage array. The storage domain designates that only the selected host or host group has access to that particular volume through the assigned LUN.
When the storage domain consists of a volume mapped to a host group, it can enable hosts with different operating systems (heterogeneous hosts), to share access to a storage volume. A host within a host group can be mapped separately to a different volume.
A storage domain can contain up to 256 volumes. A volume can be included in only one storage domain and each LUN, from 0 to 255, can only be used once per storage domain.
Note: Not all operating systems support up to 256 LUN IDs. See the documentation for your operating system for more information.
A default storage domain exists to include the following:
Any volumes within the default storage domain can be accessed by all hosts and host groups within that storage domain.
Creating an explicit volume-to-LUN mapping for any host or host group and volume within the default storage domain causes the management software to remove the specified host or host group and volume from the default storage domain and crate a new separate domain.
The array management software supplies eight storage domains. You must obtain a license for additional storage domain support.
Before creating a storage domain, you should perform the following tasks:
A host included in a storage domain, either as an individual host or as a member of a host group, can have access to storage volumes only if it one or more initiators.
There are several ways to create a storage domain:
Create a storage domain at this time by mapping the volume to either the default storage domain or to hosts or hosts that you have already created.
Create a storage domain from the Volume Summary page to map existing standard volumes to existing hosts or host groups. Use the Volume Details page if you want to map or remap the volume after reviewing the volume details.
Create a storage domain from the Host Details page or Host Groups Details page if you want to map several standard volumes or snapshot volumes to one host or host group.
Create a storage domain from the Snapshot Summary page or Snapshot Details page if you want to map existing snapshot volumes to existing hosts or host groups. Use the Snapshot Details page if you want to map or remap the snapshot volume after reviewing the snapshot volume details.