How does SRM work?By Deni Connor
Storage resource management (SRM) software collects information on the heterogeneous resources - operating systems, host computers and SAN devices such as Fibre Channel switches and storage arrays - on shared storage networks.
According to Gartner, SRM packages should contain:
* A repository for the resources that are discovered;
* The ability to plan capacity and manage it;
* Performance, event and quota management;
* SAN design, provisioning and the automation of workflow;
* Root-cause analysis, change and configuration management; and
* Reporting and chargeback.
Once storage resources are discovered, they need to be stored in a database so that the state of the SAN can be assessed and provide information for historical and future trending. Data is stored in the repository by size, creation date and owner if it is a file, and by capacity and performance if it is a storage system.
Capacity management includes the ability to identify use of resources and to reclaim unused capacity if necessary. The software should also let the user determine when it is necessary to acquire more disk space or improve performance. It should predict storage utilization by business unit, application, user, server or department.
In managing performance, SRM software should look at the relationships between applications, servers, host bus adapters, switches and storage arrays, and let users monitor and diagnose performance problems and bottlenecks caused by different resources in the SAN or by configuration changes.
Quota management lets the IT administrator set disk limits by user, department, group or business unit and monitor the disk for out-of-disk conditions. Within quota management, rules can be created that enforce the type of files being saved.
Event management is the recognition of triggers or alerts that may signal out-of-disk events or performance issues. It is important that the event management function be integration with systems or network management packages.
SRM packages should also include tools that make it easier for the IT administrator to provision more storage when the quota management and capacity management pieces indicate it is necessary. Provisioning includes the ability to assign storage volumes to host computers and applications or to delete these relationships or change them. SRM should also include tools that allow SAN design verification. Automating the workflow of commonly occurring operations is also an important feature of an SRM package because it allows the dynamic operation of error-prone manual processes.
Some packages - like those from Onaro and Akorri, which focus on performance and change management - offer only a subset of SRM functions. Others such as Monosphere and TeraCloud focus on capacity planning. Change management software allows IT to manage changes to the SAN, identify unplanned changes and create alerts when changes are made. This capability, according to Gartner, may include the ability to take snapshots before changes are made. If errors occur as the result of the changes, the state of the system can be rolled back.
Similarly, root-cause analysis allows IT to identify the reason for a problem and avoid willy-nilly troubleshooting.
Finally, an SRM package must have three other capabilities - reporting, chargeback and a central management console. Reporting is necessary so the IT administrator and upper management can assess the effectiveness of the SAN. Chargeback is a recommended function in that it allows IT to charge departments, business units or groups of users for their use of storage resources.
In addition, each SRM package should have the ability to manage storage resources from a Web-based management console, scalability to adapt to large or small environments and integration with systems and network management packages.
SRM packages should span a variety of operating systems - Windows, Linux and Unix servers - as well as a wide variety of storage systems and applications such as messaging and databases.
This story, "Guide to Storage Resource Management" was originally published by Network World.