Full-System Cold Restore (ON-Bar) (SAP Library - SAP Database Guide: Informix (BC-DB-INF-DBA))

Full-System Cold Restore (ON-Bar)

Purpose

This section describes how to perform a full-system cold restore of your Informix database, if you use ON-Bar as your data recovery tool (that is, for your database and logical-log backups).

If you want to stop the restore at a specific point, you can specify a "Point-in-Time" (PIT) or a "Point-in-Log" (PIL) during the logical restore stage. ON-Bar and the database server automatically know which logical logs to restore.

Prerequisites

See Getting Started with Restore to make sure that you have already correctly identified the problem and chosen the right kind of restore.

Before you start, see Preparing for a Full-System Cold Restore (ON-Bar).

Process Flow

If there are logical logs that were not backed up at the time of the failure, you can salvage the logical logs. ON-Bar performs this by default for a cold restore, unless you specify only a physical restore (see next step).

You perform physical restore for a full-system cold restore.

You perform logical restore for a full-system cold restore.

Importance of Stages in Full-System Cold Restore (ON-Bar)

Stage	Stage required?	Effects of leaving out stage
Salvage logical log	Not always	Your database might be less up-to-date. You lose any transactions held in the logical log not backed up at time of failure.
Physical restore	Yes	You must always do at least a physical restore.
Logical restore	Only with a restore from a storage-space backup	Storage-space backup: database is inconsistent. Whole-system backup: database is less up-to-date

Result

Your database is now restored and can be used productively again.

See also:

Informix documentation