IBM 000-8697 User Manual

IBM Informix OnLine Database Server Administrator’s Guide

Create the mirror chunk on a separate device from the primary chunk.
Ideally, the mirror chunk device should be managed by a different controller
than the controller that manages the primary chunk.

Mirroring begins immediately unless the chunk contains a logical log file. If
this is the case, mirroring begins in this chunk as soon as you create a level-0
archive.

You cannot start mirroring in a dbspace that contains a logical log file while
a level-0 archive is in progress.

When you end mirroring, all mirror chunks are released. These chunks are
immediately available for reassignment to other blobspaces or dbspaces.

You cannot end mirroring in a blobspace or dbspace that contains a primary
chunk that is down (status

D

).

Blobspaces and dbspaces can be described by their mirroring flags:

A mirroring flag for every OnLine blobspace and dbspace is displayed on the
first screen that appears when you select the Dbspaces menu, Mirror option.
An asterisk to the right of the

Mirror

field indicates that one or more chunks

in the blobspace or dbspace is down.

Y

Blobspace or dbspace is mirrored.

N

Blobspace or dbspace is not mirrored.

X

Dbspace contains a logical log; mirroring takes effect as soon as you
create a level-0 archive.