Data Migration Tool
From an end user perspective the data migration strategy applied for each application aims to achieve the following:
* Data integrity following data migration. The agreed application data must not be corrupt or incompatible following the data migration exercise.
* The opportunity to iteratively identify and cleanse data that is corrupt on the existing application(s). The aim is to give the users one or more 'iterative' opportunities to identify corrupt data, and then rectify it in the existing applications, or automatically cleanse the data within the bespoke data migration functionality.
* The option of data weeding within the data migration mechanism. This involves the identification of migration candidates, such that obsolete data (i.e. non-candidate data) is not migrated into the target database.
* The ability to inspect, but not maintain, data that has been archived either before or during the live data migration run. This feature is particularly important where users will no longer have access to their 'source' application(s) and data following migration.
There are many different ways to perform data migration depending on client requirements and Doriath Technology best practices, external system availability, migration complexity and the actual data volume. No matter what approach is chosen, at the beginning of data migration process, the source databases must be examined to make an initial evaluation of the scope of the data cleansing and data conversion activity required. This examination of the source database will provide the basis for the data migration strategy.
There are number of data migration cutover approaches that can be considered depending on situation. These are;
* Big-Bang Migration: All data from existing systems are migrated over to chosen target platform at once during a predetermined migration cutover duration. For instance, a long weekend can be chosen for the migration activity and at the end of this period, the old systems will stop its operation and the new system will be in production. Even though, there are number of risks involved with this approach, looking at the benefits and simplicity, it is always a good candidate.
* Horizontal Migration: According to this strategy, part of data to be migrated (such as subset of entire customer base) is migrated to chosen system. For instance, we might decide that only prepaid or postpaid subscribers are moved to target system. Or, only part of the subscribers (within a customer number range) is migrated to target platform.
* Vertical Migration: According to this approach, only some functionality will exist in the target system. For instance, for a first step, new system can be used only for trouble ticketing purposes or only for invoicing of Corporate customers.
Operational, as well as functional migration is very important. Doriath Technology observes in the migration process (no matter whichever migration strategy is chosen);
* No disruption for the end customer;
- End customers will continue to use services (call center, complaints handling, etc.) during cutover process.
- Data generated/changed will be retrofitted to migrated systems after the cutover.
* Minimal or no disruption to business functions;
- Event though, Doriath Technology approach is to provide seamless migration for business functions, some of sub-systems might be temporarily unavailable during cutover process.
* Minimize old and new platform coexistence time;
- This will be as a result of Doriath Technology and client workshops on the migration strategy. For each migration option, there are certain advantages and disadvantages.
Following is Doriath Technology migration process;
* Define multiple possible migration strategies
* Data profiling
* Data mapping
- Current applications (data structures, identify critical validation points)
- Current infrastructure (HW, Database)
- Define future infrastructure requirements
* Determine migration requirements
* Determine final migration strategy
* Create migration project plan and mobilize resources
* Create migration architecture
* Develop test plans and acceptance criteria
* Develop/configure migration scripts
* Run pre-validation tests
* Data Extraction
* Data Assessment
* Data Alignment
* Data Load
* Verify migration completion
* Run post-validation tests
* Perform knowledge transfer
* Create report on migration statistics
* Migration close out meeting
During all migration process stages (Plan, Migrate, Validate) Doriath Technology undertakes:
* Control of the process
* Control of the deliverables
* Control of resources
* Risk mitigation
* Apply quality measures