Operating systems and backup interoperability issues

As IT professionals we face an ever increasing need for enterprise and departmental information storage strategies. Fibre Channel (FC), storage area networks, network attached storage, IP and SCSI-based storage solutions offer particular advantages to the storage consumer. However, we need to understand that a storage decision doesn''t have to be technologically exclusive. Multiple solutions can compliment one another, or conversely can add unnecessary administration and operations overhead, if the issue of interoperability is not addressed.

Some of the issues that need to be considered are the sharing of storage among different operating systems, along with the associated OS-based file system and volume management tools. Sharing the same disk storage arrays with UNIX and non-UNIX servers in a FC SAN, for example, can be problematic due to LAN contention issues.

UNIX and non-UNIX-based servers can be attached to the same FC SAN through hardware techniques called zoning and LAN masking, but they can create increased management and cost issues of their own.

Layering additional switch-based or third-party SAN management software on top of complex OS utilities, such as file system and volume management tools, can cause management and operation conflicts as well as system errors. Such conflicts have prevented industry wide acceptance of SAN management tools.

Tape backup and disaster recovery requirements also need to be addressed. SAN and NAS storage solutions can be backed up to the same tape devices using techniques such as IP over FC and NDMP (Network Data Management Protocol) network agents. However, industry experts are of the opinion that these solutions are complex and not widely adopted. They raise significant interoperability and administration concerns, primarily due to the lack of any generalized standards and industry expertise. On the other hand, using multiple backup solutions add additional cost and administrative overhead.

Some major open SAN solutions

Amsal Infotech managing director Girish Baliga says, "We do no have a standard set of process and methodology to verify the operation of large and heterogeneous SANs." He said, "Since enterprises have a lot of configurations and many applications running on different Operating Systems (OS), we need to work on open standardization. Also one needs to go through interoperability testing process to ensure that the back-ups are up and running effectively."

Explains Hitachi Data Systems business development manager Vivekanand, "We have always believed in Open SANs and rather collaborate than control. We collaborate with the best breed of SAN component vendors and work with the industry to create standards that everyone can build with".

According to him, Hitachi has forged strategic partnership with leading industry vendors like Microsoft and McDATA Corp to introduce combination of hardware, software and services. Called Microsoft Trusted Solution Platform (MTSP), it delivers highly available scalable solutions for organizations running MS Exchange SQL server in a Windows NT/2K Advanced Server environments. This Freedom Data Networks model of Hitachi extends to the openness of multiple operating systems.

Concurs Sun Microsystems’ director-systems engineering Anil Velluri, "Management applications must be tailored to recognize each new device -- whether that device is a disk array, server, database, router or any other application." He added that because there were few industry-standard infrastructures for developers to leverage, the need for creating new management applications that were platform independent and managing complex distributed environments such as storage networks had risen.

Sun’s ‘Jiro’ is one such technology, which makes it possible to deliver intelligent management services for networked devices through a platform-independent, industry-defined development environment, he said. Using the principles of Java technology, ‘Jiro’ provides an innovative architecture for connecting and managing complex distributed environments such as storage networks. With its network-centric model for development and deployment, Jiro brings higher levels of interoperability, adaptability and manageability to today''s enterprise networks.

Interoperability Testing

So what are the typical interoperability testing processes that enterprises have to undergo. Well, according to the storage experts, storage solution providers carry out testing process of real back-ups using leading software packages. When building back-up solutions into SANs, both the access of online storage as well as near-line backup are critical.

Ironically, what a typical testing process involves is that while back-up is running, one needs to do processes that are perturbing to the system such as failing redundant disk drives, failing data paths and such error measures. That''s precisely are the codes that really need to be exercised in these tests and most of the codes in an array controller are error-handling codes that deal with operation in certain eventuality.

We need to understand that no single storage solution is capable of supporting all users and applications. Different solution types can coexist, but require different management skills and possibly, different management tools. Component interoperability should be verified and tested prior to deployment. As experts feel, enterprises have to consult vendor-independent, experienced storage experts when considering to adopt storage solutions.