Many mainframe installations have large quantities of legacy data stored in tape
archives. When migrating applications off the mainframe onto midrange platforms,
the question arises what to do with the legacy tape data. Much of the data will
never be accessed but must be maintained for compliance. However, some of the data
may require easy access by the migrated applications.
After the mainframe decommission there will be no hardware or software for accessing
tape data and outsourcing solutions may turn out to be quite expensive. One should
also not forget that in order to allow access to mainframe tape data a significant
amount of “control metadata” is needed.
Several alternative approaches to mainframe data conservation may be considered,
namely:
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Dataset Migration Approach – Datasets are extracted from
all the tapes and moved to disk files on the midrange platform (a Dataset Catalog
is also created). This process, if performed on-line, can consume large quantities
of compute resources such as tape drives and CPU cycles. Some data sets may also
require a time-consuming conversion process (e.g. performing EBCDIC to ASCII or
copybook directed conversion).
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Control Metadata Migration Approach - The mainframe metadata
from the System Catalog, TMS, and if present the VTS is exported while the data
is kept in its original “tape format”. The “preserved” metadata can then be used
to locate desired datasets in the future, which can be extracted from the tapes
via a service using non-native tools. This solution is the least expensive as far
as the migration is concerned, but relies on an external service for the “vaulting”
of the original tape media and the on-demand extraction of the needed data.
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Deep Archive Migration Approach - This solution involves
the creation of a “deep archive” of the original tapes in the form of virtual tapes
stored on disk storage (e.g. VTL, MAID, etc.) or stacked on high-capacity state-of-the-art
media (e.g. LTO-4, T10K, etc.). This significantly reduces the footprint of the
conserved data and protects it from technology obsolescence over its useful life.
Data access at the virtual tape level and the dataset level is ensured by the presence
in the “deep archive” of the control metadata in consolidated form.
Only an in-depth analysis of each situation and its specific requirements will permit
the identification of the best solution.
Leveraging its experience and the availability of sophisticated tools (hardware
and software) developed and employed as part of its media conversion and data migration
business, Data Strategies is offering a comprehensive set of services, (the Mainframe
Data Conservation Services, or MDCS), specifically targeted to long-term mainframe
tape data conservation.
These services vary with the customer’s specific environment, but share the common
objective of allowing the ‘removal’ of the mainframe while maintaining the ability
to identify and access any ‘data’ of interest. This goal is achieved by providing
an alternative (to the mainframe) hardware and software environment specifically
designed for legacy tape data.
In particular the MDCS provide for:
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Analysis of customer’s environment. This task is aimed at quantifying the amount
of mainframe tape data to be ‘conserved’, qualifying the data on the base of type,
source, retention and security requirements, and identifying the associated control
metadata. It is also aimed at identifying the type of storage media, tape drives,
libraries involved.
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Selection of optimal solution. Based on the results of the analysis, the solution
that best meets the functional and cost requirements is identified and a detailed
proposal is prepared.
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Transfer of Control Metadata. This task consolidates and ‘moves’ all TMS, System
Catalog, and application specific metadata from the mainframe to MDCS Data Base.
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Optional Storage of Legacy Tapes. Customer has the option of keeping the physical
storage of the legacy tapes with a company of his choice or of transferring them
into the custody of Data Strategies.
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Optional Datasets Migration. This task uses the MDCS Data Base to extract all datasets
from the mainframe tapes and store them on disk storage. A migrated dataset catalog
is build as part of the process.
-
Optional Deep Archival of Legacy Tapes. This task creates virtual tapes stored on
disk storage or stacked on high-capacity state-of-the-art media and builds the associated
MDCS database.
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The DataArk Appliance. This is an appliance that provides a long-term repository
for mainframe tape data and convenient data access by migrated applications. Based
on open-system technology that can easily evolve with time to guarantee its long-term
operability, it contains a set of integrated software tools capable of retrieving,
extracting, restoring/converting any data of interest from the ‘conserved’ legacy
tapes (or virtual tapes).
The Mainframe Data Conservation Services offered by Data Strategies relieve the
customer from the hassle and cost of maintaining legacy hardware, keeping maintenance
contracts for unsupported software, and retaining staff with skills of decreasing
value to the organization.