Note: When discussing disruptiveness, we don't consider any interruptions that may be caused by adding the new DS6000 LUNs to the host and later by removing the old storage. They vary too much from operating system to operating system, even from version to version. However, they have to be taken into account, too.
Once it is decided which method (or methods) to use, the migration process starts with a very careful planning phase. Items to be taken into account during migration planning include:
Availability of all the required hardware and software.
Installation of the new and removal of the old storage.
Installation of drivers required for the new storage.
A test of the new environment.
The storage configuration before, during, and after the migration.
The time schedule of the whole process, including the scheduling of outages.
Does everyone involved have the necessary skills to perform their tasks?
Additional information about data migration to the DS6000 can be found in the DS6000 Introduction and Planning Guide,
Exceptional care must be exercised in data sharing (clustered) environments. If data is shared between more than one host, all of them have to be made aware of the changes in the configuration, even if the migration is only performed by one of them. Refer to the documentation of your clustering solution for ways to propagate configuration changes throughout the cluster.
Note: IBM Global Services can assist you in all phases of the migration process with professional skill and methods.
15.2 Comparison of migration methods
There are numerous methods that can be used to migrate data from one storage system to another. We briefly describe the most common ones and list their advantages and disadvantages in the following sections.
Note: The IBM iSeries platform with the OS/400 and i5/OS operating systems has a different approach to data management than the other open systems. Therefore different strategies for data migration apply. Refer to Appendix B, “Using the DS6000 with iSeries” on page 329.
15.2.1 Host operating system-based migration
Data migration using tools that come with the host operating system has these advantages:
No additional cost for software or hardware.
System administrators are used to using the tools.
Reasons against using these methods could include:
Different methods are necessary for different data types and operating systems.
Chapter 15. Data migration in the open systems environment | 291 |
