Overview of Enterprise Storage Management

This topic describes the major hardware components and the software components in the Enterprise Storage Management environment. This topic also describes the two different network management connections that you can use to manage .

What Are the Major Hardware Components?

The management of your storage subsystems occurs over the network. The items in the table are the major hardware components that are connected to the network.

Hardware Components

Hardware Component Description
Storage subsystem A storage entity that is managed by the storage management software. A storage subsystem consists of a collection of both physical components and logical components. Physical components include disk drives, controllers, fans, and power supplies. Logical components include arrays and logical drives. A storage subsystem can span multiple physical enclosures.
Storage management station The computer that you use to manage the storage subsystems on your network.
Network management station (optional)

A console with installed -compliant network management software. The network management station receives and processes information about network storage subsystems that it manages. The information is in a form that is supported by the management information base (MIB) that the network management station uses.

The storage management software provides information about critical storage subsystem events, using , to a configured network management station.

Host A computer that runs one or more applications that access the storage subsystem over the I/O path.
BOOTP or BOOTP-compliant DHCP server

A BOOTP or BOOTP-compliant DHCP server assigns the network-specific information for each controller. Network-specific information is information such as an IP address or a name.

The BOOTP or BOOTP-compliant DHCP server is optional. It is not required if you manage all of your storage subsystems using the host-agent.

File server (optional) The storage management software optionally can be stored on a central file server. Management stations on the network can then access the storage management software remotely.
What are the Major Software Components?

The storage management software has three major components:


Note:

The host-agent management software is optional. The host-agent management software is required only if you intend to manage a storage subsystem through a host.

Client Management

The client management piece of the storage management software has two main windows: the Enterprise Management Window (EMW) and the Subsystem Management Window (SMW).

The EMW is the first window that appears when you start the software. You use the EMW to add and discover the storage subsystems that you want to manage and to provide a comprehensive view of those storage subsystems. A list of storage subsystems is stored in a local . After you have added the storage subsystems, you use the EMW primarily for monitoring and alert notification of non-optimal storage subsystems. You also use the EMW to launch the SMW for a specified storage subsystem. All storage subsystem-specific management tasks are provided in the SMW.

You use the SMW to manage the physical components and logical components that comprise a storage subsystem. Management tasks include configuring a storage subsystem, maintaining a storage subsystem, and recovering if a physical component has a failure. Physical components include disk drives, controllers, fans, and power supplies, as well as the cables that connect the physical components. Logical components include logical drives and arrays. The SMW is specific to an individual storage subsystem. Therefore, you can manage only a single storage subsystem from the SMW. However, you can launch other SMWs to manage other storage subsystems.

Host-Agent Management Software

The host-agent management software is optional software that you can install on one or more hosts that are connected to the storage subsystems. The host-agent management software, along with the Ethernet connection on the host, provides you with another network management connection to the storage subsystem rather than using the individual Ethernet connections on each controller in the storage subsystem. For more information about methods for connecting storage subsystems to networks, see “Out-of-Band Storage Subsystems” and “In-Band Storage Subsystems.”

Your can communicate with a storage subsystem through the host that has host-agent management software installed. The host-agent management software takes requests from the storage management station through the Ethernet connection to the host and sends the requests to the controllers in the storage subsystem through the I/O connections between the host and the storage subsystem.

Multi-Path Driver Software

A multi-path driver also can be called an I/O path failover driver. There is typically a redundant pair of active controllers in a storage subsystem. When you create a logical drive in the storage subsystem, one of the controllers is automatically or manually chosen to “own” the logical drive and control the I/O between the logical drive and the application host along the I/O path.

When a component along the I/O path to a controller or the controller itself fails, ownership of the logical drives that had been assigned to that controller will automatically transfer to the other controller in the pair. The multi-path driver manages this failover process.

What Are the Different Ways to Manage a Storage Subsystem?

The storage management software manages all storage subsystems over the network. For increased connectivity, you can manage a storage subsystem using any combination of out-of-band, in-band, or multiple in-band network management connections. You can use a combination of out-of-band and in-band connections, but this combination is recommended because you would use three Ethernet connections. The Ethernet connection you would use are one to each controller and one through the host.

When you configure more than one network management connection into a storage subsystem, the storage management software is aware of each connection and automatically chooses a connection when you attempt to manage the storage subsystem by launching the SMW. If a particular connection is currently not responding, the software tries all other configured network management connections into that storage subsystem.

Out-of-Band Storage Subsystems

The controllers in the storage subsystem are managed directly over the network through the Ethernet connection on each controller in the storage subsystem. To manage the storage subsystem through these Ethernet connections, you must define the IP address for each controller or the host name for each controller, and attach a cable to the Ethernet connections on the storage subsystem.

In-Band Storage Subsystems

The controllers in the storage subsystem are managed through an Ethernet connection on a host instead of using the Ethernet connections on each controller. The host-agent management software on the host, described previously, facilitates communication between the management station and the host-agent management software on the host and then use the storage management software to include the host.