NonStop NS-Series Database Migration Guide

HP Integrity NonStop NS-Series Database Migration Guide—540469-001
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Falling Back an SQL/MX, SQL/MP, or
Enscribe Database
Those for whom business continuity is especially important should be prepared to fall
back their database from the Integrity NonStop NS-series system to the NonStop
S-series system if unforeseen problems make it necessary. The objective is to quickly
and successfully get the latest good version of the database on the NonStop S-series
system with little or no interruption to applications and end users.
When you use RDF or an equivalent third-party database replication product to migrate
your SQL/MP, SQL/MX, or Enscribe database to the Integrity NonStop NS-series
system, you can leverage the original primary database for this purpose. If fallback
becomes necessary before the Integrity NonStop NS-series system is designated the
primary database, no intervention is required because the NonStop S-series system is
still the primary database. If fallback becomes necessary after the Integrity NonStop
NS-series system is designated the primary database, you need only start up the
applications on the NonStop S-series system, make the NonStop S-series system the
primary database, and bring down the Integrity NonStop NS-series system. For more
information, see Migration by Online Database Replication on page 2-2.
If you do not use a database replication product or Escort SQL to migrate and fall back
your database, you cannot recover the latest version of the database. You can use
tools such as BACKUP/RESTORE or Backup and Restore 2 to back up and restore a
recent copy of the database to the NonStop S-series system, but database migration
with these tools can be relatively time consuming and will not allow uninterrupted
online access to the database.
For information about falling back an SQL/MX database to an earlier version of
SQL/MX or falling back to an SQL/MP database, see the SQL/MX Database and
Application Migration Guide.